diff --git a/addr.c b/addr.c
index abf3e3d97..b1c08bc34 100644
--- a/addr.c
+++ b/addr.c
@@ -396,7 +396,7 @@ addr_pton_cidr(const char *p, struct xaddr *n, u_int *l)
 	if ((mp = strchr(addrbuf, '/')) != NULL) {
 		*mp = '\0';
 		mp++;
-		masklen = strtoul(mp, &cp, 10);
+		masklen = strtoul(mp, &cp, 10); // CodeQL [SM02313]: strtoul will initialize cp
 		if (*mp < '0' || *mp > '9' || *cp != '\0' || masklen > 128)
 			return -1;
 	}
diff --git a/auth2-passwd.c b/auth2-passwd.c
index cc12cfbc1..b7c473618 100644
--- a/auth2-passwd.c
+++ b/auth2-passwd.c
@@ -66,7 +66,7 @@ userauth_passwd(struct ssh *ssh, const char *method)
 
 	if (change)
 		logit("password change not supported");
-	else if (PRIVSEP(auth_password(ssh, password)) == 1)
+	else if (PRIVSEP(auth_password(ssh, password)) == 1) // CodeQL [SM01714] false positive: password is null terminated
 		authenticated = 1;
 	freezero(password, len);
 	return authenticated;
diff --git a/channels.c b/channels.c
index 6d56dda3d..6b7d259a4 100644
--- a/channels.c
+++ b/channels.c
@@ -1175,8 +1175,9 @@ x11_open_helper(struct ssh *ssh, struct sshbuf *b)
 		return 0;
 
 	/* Parse the lengths of variable-length fields. */
-	ucp = sshbuf_mutable_ptr(b);
-	if (ucp[0] == 0x42) {	/* Byte order MSB first. */
+	if ((ucp = sshbuf_mutable_ptr(b)) == NULL) // fix CodeQL SM02311
+		return 0;
+	if (ucp[0] == 0x42) { /* Byte order MSB first. */
 		proto_len = 256 * ucp[6] + ucp[7];
 		data_len = 256 * ucp[8] + ucp[9];
 	} else if (ucp[0] == 0x6c) {	/* Byte order LSB first. */
@@ -1291,6 +1292,10 @@ channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
 	if (have < len)
 		return 0;
 	p = sshbuf_ptr(input);
+	if (p == NULL) { // fix CodeQL SM02311 
+		error("channel %d: invalid input", c->self);
+		return -1;
+	}
 
 	need = 1;
 	/* SOCKS4A uses an invalid IP address 0.0.0.x */
@@ -1324,7 +1329,7 @@ channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
 	}
 	have = sshbuf_len(input);
 	p = sshbuf_ptr(input);
-	if (memchr(p, '\0', have) == NULL) {
+	if (p == NULL || memchr(p, '\0', have) == NULL) { // fix CodeQL SM02311 
 		error("channel %d: decode socks4: unterminated user", c->self);
 		return -1;
 	}
@@ -1342,7 +1347,7 @@ channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
 	} else {				/* SOCKS4A: two strings */
 		have = sshbuf_len(input);
 		p = sshbuf_ptr(input);
-		if (memchr(p, '\0', have) == NULL) {
+		if (p == NULL || memchr(p, '\0', have) == NULL) { // fix CodeQL SM02311 
 			error("channel %d: decode socks4a: host not nul "
 			    "terminated", c->self);
 			return -1;
@@ -1406,7 +1411,7 @@ channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
 
 	debug2("channel %d: decode socks5", c->self);
 	p = sshbuf_ptr(input);
-	if (p[0] != 0x05)
+	if (p == NULL || p[0] != 0x05) // fix CodeQL SM02311 
 		return -1;
 	have = sshbuf_len(input);
 	if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
@@ -1559,6 +1564,8 @@ channel_pre_dynamic(struct ssh *ssh, Channel *c)
 	}
 	/* try to guess the protocol */
 	p = sshbuf_ptr(c->input);
+	if (p == NULL) // fix CodeQL SM02311 
+		return;
 	/* XXX sshbuf_peek_u8? */
 	switch (p[0]) {
 	case 0x04:
@@ -1621,6 +1628,8 @@ channel_before_prepare_io_rdynamic(struct ssh *ssh, Channel *c)
 		return;
 	/* try to guess the protocol */
 	p = sshbuf_ptr(c->output);
+	if (p == NULL) // fix CodeQL SM02311 
+		return;
 	switch (p[0]) {
 	case 0x04:
 		/* switch input/output for reverse forwarding */
diff --git a/contrib/win32/win32compat/ansiprsr.c b/contrib/win32/win32compat/ansiprsr.c
index a3bfaa5dc..e96a1b64d 100644
--- a/contrib/win32/win32compat/ansiprsr.c
+++ b/contrib/win32/win32compat/ansiprsr.c
@@ -670,7 +670,7 @@ ParseANSI(unsigned char * pszBuffer, unsigned char * pszBufferEnd, unsigned char
 					}
 				} else if (iParam[0] == 6) {
 					char * szStatus = GetCursorPositionReport();
-					if (respbuf != NULL) {
+					if (szStatus != NULL && respbuf != NULL) {
 						*respbuf = szStatus;
 						if (resplen != NULL)
 							*resplen = strlen(szStatus);
diff --git a/contrib/win32/win32compat/console.c b/contrib/win32/win32compat/console.c
index 9bc0017e4..396bd7f63 100644
--- a/contrib/win32/win32compat/console.c
+++ b/contrib/win32/win32compat/console.c
@@ -182,7 +182,7 @@ ConEnterRawMode()
 	if (FALSE == isConHostParserEnabled || !SetConsoleMode(GetConsoleOutputHandle(), dwAttributes)) /* Windows NT */
 		isAnsiParsingRequired = TRUE;
 			
-	GetConsoleScreenBufferInfo(GetConsoleOutputHandle(), &csbi);
+	BOOL gcsbRet = GetConsoleScreenBufferInfo(GetConsoleOutputHandle(), &csbi);
 	
 	/* We track the view port, if conpty is not supported */
 	if (!is_conpty_supported())
@@ -192,6 +192,12 @@ ConEnterRawMode()
 	 *  so that the clearscreen will not erase any lines.
 	 */
 	if (TRUE == isAnsiParsingRequired) {
+		if (gcsbRet == 0)
+		{
+			dwRet = GetLastError();
+			error("GetConsoleScreenBufferInfo on GetConsoleOutputHandle() failed with %d", dwRet);
+			return;
+		}
 		SavedViewRect = csbi.srWindow;
 		debug("console doesn't support the ansi parsing");
 	} else {
@@ -621,12 +627,17 @@ ConWriteString(char* pszString, int cbString)
 	if ((needed = MultiByteToWideChar(CP_UTF8, 0, pszString, cbString, NULL, 0)) == 0 ||
 	    (utf16 = malloc(needed * sizeof(wchar_t))) == NULL ||
 	    (cnt = MultiByteToWideChar(CP_UTF8, 0, pszString, cbString, utf16, needed)) == 0) {
-		Result = (DWORD)printf_s(pszString);
-	} else {
+		const char* pszStringConst = pszString;
+		Result = (DWORD)printf_s(pszStringConst);
+	}
+	else {
 		if (GetConsoleOutputHandle())
 			WriteConsoleW(GetConsoleOutputHandle(), utf16, cnt, &Result, 0);
 		else
-			Result = (DWORD)wprintf_s(utf16);
+		{
+			const wchar_t* utf16Const = utf16;
+			Result = (DWORD)wprintf_s(utf16Const);
+		}
 	}
 
 	if (utf16)
diff --git a/contrib/win32/win32compat/fileio.c b/contrib/win32/win32compat/fileio.c
index b99773232..b7e4e6338 100644
--- a/contrib/win32/win32compat/fileio.c
+++ b/contrib/win32/win32compat/fileio.c
@@ -1189,7 +1189,7 @@ fileio_readlink(const char *path, char *buf, size_t bufsiz)
 	}
 
 	/* allocate the maximum possible size the reparse buffer size could be */
-	reparse_buffer = (PREPARSE_DATA_BUFFER_SYMLINK)malloc(MAXIMUM_REPARSE_DATA_BUFFER_SIZE);
+	reparse_buffer = (PREPARSE_DATA_BUFFER_SYMLINK)malloc(MAXIMUM_REPARSE_DATA_BUFFER_SIZE); // CodeQL [SM02320]: DeviceIoControl will set reparse_buffer
 	if (reparse_buffer == NULL) {
 		errno = ENOMEM;
 		goto cleanup;
diff --git a/contrib/win32/win32compat/gss-sspi.c b/contrib/win32/win32compat/gss-sspi.c
index 1113d0be3..ffee6a899 100644
--- a/contrib/win32/win32compat/gss-sspi.c
+++ b/contrib/win32/win32compat/gss-sspi.c
@@ -444,8 +444,10 @@ gss_acquire_cred(_Out_ OM_uint32 *minor_status, _In_opt_ gss_name_t desired_name
 	/* determine expiration if requested */
 	if (time_rec != NULL) {
 		FILETIME current_time;
-		SystemTimeToFileTime(&current_time_system, &current_time);
-		*time_rec = (OM_uint32) (expiry.QuadPart - ((PLARGE_INTEGER)&current_time)->QuadPart) / 10000;
+		if (SystemTimeToFileTime(&current_time_system, &current_time) != 0)
+			*time_rec = (OM_uint32)(expiry.QuadPart - ((PLARGE_INTEGER)&current_time)->QuadPart) / 10000;
+		else
+			error("SystemTimeToFileTime failed with %d", GetLastError());
 	}
 
 	/* set actual supported mechs if requested */
@@ -597,8 +599,10 @@ gss_init_sec_context(
 	/* if requested, translate the expiration time to number of second */
 	if (time_rec != NULL) {
 		FILETIME current_time;
-		SystemTimeToFileTime(&current_time_system, &current_time);
-		*time_rec = (OM_uint32)(expiry.QuadPart - ((PLARGE_INTEGER)&current_time)->QuadPart) / 10000;
+		if (SystemTimeToFileTime(&current_time_system, &current_time) != 0)
+			*time_rec = (OM_uint32)(expiry.QuadPart - ((PLARGE_INTEGER)&current_time)->QuadPart) / 10000;
+		else
+			error("SystemTimeToFileTime failed with %d", GetLastError());
 	}
 
 	/* if requested, return the supported mechanism oid */
@@ -907,8 +911,10 @@ gss_accept_sec_context(_Out_ OM_uint32 * minor_status, _Inout_opt_ gss_ctx_id_t
 	/* if requested, translate the expiration time to number of second */
 	if (time_rec != NULL) {
 		FILETIME current_time;
-		SystemTimeToFileTime(&current_time_system, &current_time);
-		*time_rec = (OM_uint32)(expiry.QuadPart - ((PLARGE_INTEGER)&current_time)->QuadPart) / 10000;
+		if (SystemTimeToFileTime(&current_time_system, &current_time) != 0)
+			*time_rec = (OM_uint32)(expiry.QuadPart - ((PLARGE_INTEGER)&current_time)->QuadPart) / 10000;
+		else
+			error("SystemTimeToFileTime failed with %d", GetLastError());
 	}
 
 	/* only do checks on the finalized context (no continue needed) */
@@ -1072,6 +1078,11 @@ ssh_gssapi_krb5_userok(ssh_gssapi_client *client, char *name)
 	 * onto the next available method.
 	 */
 	struct passwd * user = getpwnam(name);
+	if (user == NULL)
+	{
+		error("sspi getpwnam failed to get user from user-provided, resolved user '%s'", name);
+		return 0;
+	}
 	if (_stricmp(client->displayname.value, user->pw_name) != 0) {
 		/* check failed */
 		debug("sspi user '%s' did not match user-provided, resolved user '%s'", 
diff --git a/contrib/win32/win32compat/inc/time.h b/contrib/win32/win32compat/inc/time.h
index 1994ea4b8..80c469310 100644
--- a/contrib/win32/win32compat/inc/time.h
+++ b/contrib/win32/win32compat/inc/time.h
@@ -1,4 +1,9 @@
 #include "crtheaders.h"
 #include TIME_H
 
+#define localtime w32_localtime
+#define ctime w32_ctime
+
 struct tm *localtime_r(const time_t *, struct tm *);
+struct tm *w32_localtime(const time_t* sourceTime);
+char *w32_ctime(const time_t* sourceTime);
diff --git a/contrib/win32/win32compat/misc.c b/contrib/win32/win32compat/misc.c
index 6e9580ce8..ce69bc08d 100644
--- a/contrib/win32/win32compat/misc.c
+++ b/contrib/win32/win32compat/misc.c
@@ -410,8 +410,10 @@ char*
 		* stop reading until reach '\n' or the converted utf8 string length is n-1
 		*/
 		do {
-			if (str_tmp)
-				free(str_tmp);			
+			if (str_tmp) {
+				free(str_tmp);
+				str_tmp = NULL;
+			}
 			if (fgetws(str_w, 2, stream) == NULL)
 				goto cleanup;
 			if ((str_tmp = utf16_to_utf8(str_w)) == NULL) {
@@ -1485,6 +1487,28 @@ localtime_r(const time_t *timep, struct tm *result)
 	return localtime_s(result, timep) == 0 ? result : NULL;
 }
 
+struct tm *
+w32_localtime(const time_t* sourceTime)
+{
+	struct tm* destTime = (struct tm*)malloc(sizeof(struct tm));
+	if (destTime == NULL)
+	{
+		return NULL;
+	}
+	return localtime_s(destTime, sourceTime) == 0 ? destTime : NULL;
+}
+
+char*
+w32_ctime(const time_t* sourceTime)
+{
+	char *destTime = malloc(26);
+	if (destTime == NULL)
+	{
+		return NULL;
+	}
+	return ctime_s(destTime, 26, sourceTime) == 0 ? destTime : NULL;
+}
+
 void
 freezero(void *ptr, size_t sz)
 {
@@ -1578,8 +1602,11 @@ am_system()
 
 	if (OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &proc_token) == FALSE ||
 		GetTokenInformation(proc_token, TokenUser, NULL, 0, &info_len) == TRUE ||
-		(info = (TOKEN_USER*)malloc(info_len)) == NULL ||
-		GetTokenInformation(proc_token, TokenUser, info, info_len, &info_len) == FALSE)
+		(info = (TOKEN_USER*)malloc(info_len)) == NULL) {
+			fatal("unable to know if I am running as system");
+	}
+
+	if (GetTokenInformation(proc_token, TokenUser, info, info_len, &info_len) == FALSE) 
 		fatal("unable to know if I am running as system");
 
 	if (IsWellKnownSid(info->User.Sid, WinLocalSystemSid))
@@ -1609,7 +1636,7 @@ lookup_sid(const wchar_t* name_utf16, PSID psid, DWORD * psid_len)
 	wchar_t* name_utf16_modified = NULL;
 	BOOL resolveAsAdminsSid = 0, r;
 
-	LookupAccountNameW(NULL, name_utf16, NULL, &sid_len, dom, &dom_len, &n_use);
+	LookupAccountNameW(NULL, name_utf16, NULL, &sid_len, dom, &dom_len, &n_use); // CodeQL [SM02313]: false positive n_use will not be uninitialized
 
 	if (sid_len == 0 && _wcsicmp(name_utf16, L"administrators") == 0) {
 		CreateWellKnownSid(WinBuiltinAdministratorsSid, NULL, NULL, &sid_len);
@@ -1663,6 +1690,12 @@ lookup_sid(const wchar_t* name_utf16, PSID psid, DWORD * psid_len)
 		debug3_f("local user name is same as machine name");
 		size_t name_size = wcslen(name_utf16) * 2U + 2U;
 		name_utf16_modified = malloc(name_size * sizeof(wchar_t));
+		if (name_utf16_modified == NULL)
+		{
+			errno = ENOMEM;
+			error_f("Failed to allocate memory");
+			goto cleanup;
+		}
 		name_utf16_modified[0] = L'\0';
 		wcscat_s(name_utf16_modified, name_size, name_utf16);
 		wcscat_s(name_utf16_modified, name_size, L"\\");
@@ -1709,15 +1742,15 @@ get_sid(const char* name)
 	}
 	else {
 		if (OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &token) == FALSE ||
-		    GetTokenInformation(token, TokenUser, NULL, 0, &info_len) == TRUE) {
+		    GetTokenInformation(token, TokenUser, NULL, 0, &info_len) == TRUE) { // CodeQL [SM02320]: GetTokenInformation will initialize info
 			errno = EOTHER;
 			goto cleanup;
 		}
 
-		if ((info = (TOKEN_USER*)malloc(info_len)) == NULL) {
+		if ((info = (TOKEN_USER*)malloc(info_len)) == NULL) { 
 			errno = ENOMEM;
 			goto cleanup;
-		}
+		};
 
 		if (GetTokenInformation(token, TokenUser, info, info_len, &info_len) == FALSE) {
 			errno = errno_from_Win32LastError();
diff --git a/contrib/win32/win32compat/shell-host.c b/contrib/win32/win32compat/shell-host.c
index d6b5ff0f1..874f27c85 100644
--- a/contrib/win32/win32compat/shell-host.c
+++ b/contrib/win32/win32compat/shell-host.c
@@ -891,7 +891,7 @@ ProcessEvent(void *p)
 	if (child_out == INVALID_HANDLE_VALUE || child_out == NULL)
 		return ERROR_INVALID_PARAMETER;
 
-	GetWindowThreadProcessId(hwnd, &dwProcessId);
+	GetWindowThreadProcessId(hwnd, &dwProcessId); // CodeQL [SM02313]: false positive dwProcessId will not be uninitialized
 
 	if (childProcessId != dwProcessId)
 		return ERROR_SUCCESS;
@@ -1114,7 +1114,7 @@ QueueEvent(DWORD event, HWND hwnd, LONG idObject, LONG idChild)
 	consoleEvent* current = NULL;
 
 	EnterCriticalSection(&criticalSection);
-	current = malloc(sizeof(consoleEvent));
+	current = malloc(sizeof(consoleEvent)); // CodeQL [SM02320]: current struct fields initialized below
 	if (current) {
 		if (!head) {
 			current->event = event;
@@ -1128,7 +1128,8 @@ QueueEvent(DWORD event, HWND hwnd, LONG idObject, LONG idChild)
 
 			head = current;
 			tail = current;
-		} else {
+		}
+		else {
 			current->event = event;
 			current->hwnd = hwnd;
 			current->idChild = idChild;
diff --git a/contrib/win32/win32compat/signal_sigchld.c b/contrib/win32/win32compat/signal_sigchld.c
index aa12e26c2..f533677c4 100644
--- a/contrib/win32/win32compat/signal_sigchld.c
+++ b/contrib/win32/win32compat/signal_sigchld.c
@@ -151,7 +151,7 @@ w32_kill(int pid, int sig)
 int
 waitpid(int pid, int *status, int options)
 {
-	DWORD index, ret, ret_id, exit_code, timeout = 0;
+	DWORD index, ret, ret_id, exit_code = 0, timeout = 0;
 	HANDLE process = NULL;
 
 	debug5("waitpid - pid:%d, options:%d", pid, options);
diff --git a/contrib/win32/win32compat/ssh-agent/agent.c b/contrib/win32/win32compat/ssh-agent/agent.c
index cd22288e1..9823d603a 100644
--- a/contrib/win32/win32compat/ssh-agent/agent.c
+++ b/contrib/win32/win32compat/ssh-agent/agent.c
@@ -198,7 +198,7 @@ agent_cleanup_connection(struct agent_connection* con)
 	if (con->client_process_handle)
 		CloseHandle(con->client_process_handle);
 
-	for (int i = 0; i < con->nsession_ids; i++) {
+	for (size_t i = 0; i < con->nsession_ids; i++) {
 		sshkey_free(con->session_ids[i].key);
 		sshbuf_free(con->session_ids[i].sid);
 	}
@@ -300,11 +300,13 @@ get_con_client_info(struct agent_connection* con)
 		goto done;
 	}
 
-	if (GetTokenInformation(client_primary_token, TokenUser, NULL, 0, &info_len) == TRUE ||
-		(info = (TOKEN_USER*)malloc(info_len)) == NULL ||
-		GetTokenInformation(client_primary_token, TokenUser, info, info_len, &info_len) == FALSE)
+	if (GetTokenInformation(client_primary_token, TokenUser, NULL, 0, &info_len) == TRUE || // CodeQL [SM02320]: GetTokenInformation will initialize info
+		(info = (TOKEN_USER*)malloc(info_len)) == NULL) 
 		goto done;
 
+	if (GetTokenInformation(client_primary_token, TokenUser, info, info_len, &info_len) == FALSE)
+		goto done;
+	
 	/* check if its localsystem */
 	if (IsWellKnownSid(info->User.Sid, WinLocalSystemSid)) {
 		con->client_type = SYSTEM;
diff --git a/contrib/win32/win32compat/termio.c b/contrib/win32/win32compat/termio.c
index 9ecd57679..1f9ac5851 100644
--- a/contrib/win32/win32compat/termio.c
+++ b/contrib/win32/win32compat/termio.c
@@ -203,8 +203,11 @@ WriteThread(_In_ LPVOID lpParameter)
 		pio->write_details.buf[pio->sync_write_status.to_transfer] = '\0';
 		if (0 == in_raw_mode) {
 			wchar_t* t = utf8_to_utf16(pio->write_details.buf);
-			WriteConsoleW(WINHANDLE(pio), t, (DWORD)wcslen(t), 0, 0);
-			free(t);		
+			if (t != NULL)
+			{
+				WriteConsoleW(WINHANDLE(pio), t, (DWORD)wcslen(t), 0, 0);
+				free(t);
+			}
 		} else {
 			processBuffer(WINHANDLE(pio), pio->write_details.buf, pio->sync_write_status.to_transfer, &respbuf, &resplen);
 			/* TODO - respbuf is not null in some cases, this needs to be returned back via read stream */
diff --git a/contrib/win32/win32compat/w32-doexec.c b/contrib/win32/win32compat/w32-doexec.c
index 469419714..41ea51ebe 100644
--- a/contrib/win32/win32compat/w32-doexec.c
+++ b/contrib/win32/win32compat/w32-doexec.c
@@ -145,9 +145,13 @@ setup_session_user_vars(wchar_t* profile_path)
 
 		if (ret != ERROR_SUCCESS) {
 			error_message = get_registry_operation_error_message(ret);
-			error("Unable to open Registry Key %s. %s", (j == 0 ? "HKEY_LOCAL_MACHINE" : "HKEY_CURRENT_USER"), error_message);
 			if (error_message)
+			{
+				error("Unable to open Registry Key %s. %s", (j == 0 ? "HKEY_LOCAL_MACHINE" : "HKEY_CURRENT_USER"), error_message);
 				free(error_message);
+			}
+			else
+				error("Unable to open Registry Key %s. %s", (j == 0 ? "HKEY_LOCAL_MACHINE" : "HKEY_CURRENT_USER"));
 			continue;
 		}
 		
@@ -168,9 +172,13 @@ setup_session_user_vars(wchar_t* profile_path)
 			}
 			else if (ret != ERROR_SUCCESS) {
 				error_message = get_registry_operation_error_message(ret);
-				error("Failed to enumerate the value for registry key %s. %s", (j == 0 ? "HKEY_LOCAL_MACHINE" : "HKEY_CURRENT_USER"), error_message);
 				if (error_message)
+				{
+					error("Failed to enumerate the value for registry key %s. %s", (j == 0 ? "HKEY_LOCAL_MACHINE" : "HKEY_CURRENT_USER"), error_message);
 					free(error_message);
+				}
+				else
+					error("Failed to enumerate the value for registry key %s", (j == 0 ? "HKEY_LOCAL_MACHINE" : "HKEY_CURRENT_USER"));
 				break;
 			}
 
@@ -251,7 +259,7 @@ setup_session_env(struct ssh *ssh, Session* s)
 		_snprintf(buf, ARRAYSIZE(buf), "%s@%s", s->pw->pw_name, getenv("COMPUTERNAME"));
 		UTF8_TO_UTF16_WITH_CLEANUP(tmp, buf);
 		/* escape $ characters as $$ to distinguish from special prompt characters */
-		for (int i = 0, j = 0; i < wcslen(tmp) && j < ARRAYSIZE(wbuf) - 1; i++) {
+		for (size_t i = 0, j = 0; i < wcslen(tmp) && j < ARRAYSIZE(wbuf) - 1; i++) {
 			wbuf[j] = tmp[i];
 			if (wbuf[j++] == L'$')
 				wbuf[j++] = L'$';
@@ -348,7 +356,7 @@ int do_exec_windows(struct ssh *ssh, Session *s, const char *command, int pty) {
 	JOBOBJECT_EXTENDED_LIMIT_INFORMATION job_info;
 	HANDLE job_dup;
 	pid_t pid = -1;
-	char * shell_command_option_local = NULL;
+	char * shell_command_option_local = NULL, *pty_cmd_cp = NULL;
 	size_t shell_len = 0;
 	/*account for the quotes and null*/
 	shell_len = strlen(s->pw->pw_shell) + 2 + 1;
@@ -387,21 +395,26 @@ int do_exec_windows(struct ssh *ssh, Session *s, const char *command, int pty) {
 		char *pty_cmd = NULL;
 		if (command) {
 			size_t len = strlen(shell) + 1 + strlen(shell_command_option_local) + 1 + strlen(command) + 1;
-			pty_cmd = calloc(1, len);
-
-			strcpy_s(pty_cmd, len, shell);
-			strcat_s(pty_cmd, len, " ");
-			strcat_s(pty_cmd, len, shell_command_option_local);
-			strcat_s(pty_cmd, len, " ");
-			strcat_s(pty_cmd, len, command);
+			pty_cmd_cp = pty_cmd = calloc(1, len);
+			if (pty_cmd != NULL)
+			{
+				strcpy_s(pty_cmd, len, shell);
+				strcat_s(pty_cmd, len, " ");
+				strcat_s(pty_cmd, len, shell_command_option_local);
+				strcat_s(pty_cmd, len, " ");
+				strcat_s(pty_cmd, len, command);
+			}
 		} else {
 			if (shell_arguments) {
 				size_t len = strlen(shell) + 1 + strlen(shell_arguments) + 1;
 				pty_cmd = calloc(1, len);
 
-				strcpy_s(pty_cmd, len, shell);
-				strcat_s(pty_cmd, len, " ");
-				strcat_s(pty_cmd, len, shell_arguments);
+				if (pty_cmd != NULL)
+				{
+					strcpy_s(pty_cmd, len, shell);
+					strcat_s(pty_cmd, len, " ");
+					strcat_s(pty_cmd, len, shell_arguments);
+				}
 			}
 			else
 				pty_cmd = shell;
@@ -547,6 +560,8 @@ cleanup:
 		free(shell);
 	if (job)
 		CloseHandle(job);
+	if (pty_cmd_cp)
+		free(pty_cmd_cp);
 
 	return ret;
 }
diff --git a/contrib/win32/win32compat/w32fd.c b/contrib/win32/win32compat/w32fd.c
index 24ef3697c..ed9309d54 100644
--- a/contrib/win32/win32compat/w32fd.c
+++ b/contrib/win32/win32compat/w32fd.c
@@ -114,13 +114,13 @@ fd_table_initialize()
 	/* decode fd state if any */
 	{
 		char *posix_fd_state;
-		_dupenv_s(&posix_fd_state, NULL, POSIX_FD_STATE);
+
 		/*TODO - validate parent process - to accomodate these scenarios -
 		* A posix parent process launches a regular process that inturn launches a posix child process
 		* In this case the posix child process may misinterpret POSIX_FD_STATE set by grand parent
 		*/
 
-		if (NULL != posix_fd_state) {
+		if ((_dupenv_s(&posix_fd_state, NULL, POSIX_FD_STATE) == 0) && (NULL != posix_fd_state)) {
 			fd_decode_state(posix_fd_state);
 			free(posix_fd_state);
 			_putenv_s(POSIX_FD_STATE, "");
diff --git a/contrib/win32/win32compat/w32log.c b/contrib/win32/win32compat/w32log.c
index b8cf3f9f7..98ae2949f 100644
--- a/contrib/win32/win32compat/w32log.c
+++ b/contrib/win32/win32compat/w32log.c
@@ -124,7 +124,7 @@ openlog_file()
 				goto cleanup;
 		}
 		else {
-			tmp_identity = malloc(wcslen(tail) * sizeof(wchar_t));
+			tmp_identity = malloc(wcslen(tail) * sizeof(wchar_t)); // CodeQL [SM01952]: false positive enough space for null terminator provided
 			if (!tmp_identity)
 				goto cleanup;
 			if (wcsncpy_s(tmp_identity, wcslen(tail), tail + 1, wcslen(tail) - 5) != 0) {
diff --git a/contrib/win32/win32compat/win32_groupaccess.c b/contrib/win32/win32compat/win32_groupaccess.c
index 6b7481dd4..a8beecdd0 100644
--- a/contrib/win32/win32compat/win32_groupaccess.c
+++ b/contrib/win32/win32compat/win32_groupaccess.c
@@ -95,7 +95,7 @@ get_user_groups()
 	DWORD group_size = 0;
 	if (GetTokenInformation(logon_token, TokenGroups, NULL, 0, &group_size) == 0
 		&& GetLastError() != ERROR_INSUFFICIENT_BUFFER ||
-		(group_buf = (PTOKEN_GROUPS)malloc(group_size)) == NULL) {
+		(group_buf = (PTOKEN_GROUPS)malloc(group_size)) == NULL) { // CodeQL [SM02320]: GetTokenInformation will initialize group_buf
 		debug3("%s: GetTokenInformation() failed: %d", __FUNCTION__, GetLastError());
 		errno = EOTHER;
 		goto cleanup;
diff --git a/ed25519.c b/ed25519.c
index 767ec24d6..74caeffa9 100644
--- a/ed25519.c
+++ b/ed25519.c
@@ -106,7 +106,7 @@ int crypto_sign_ed25519_open(
     const unsigned char *pk
     )
 {
-  unsigned int i;
+  unsigned long long i; // fix CodeQL SM01735
   int ret;
   unsigned char t2[32];
   ge25519 get1, get2;
diff --git a/gss-serv.c b/gss-serv.c
index 8774ca3c6..6ff98e27e 100644
--- a/gss-serv.c
+++ b/gss-serv.c
@@ -102,7 +102,11 @@ ssh_gssapi_acquire_cred(Gssctxt *ctx)
 	gss_OID_set oidset;
 
 	if (options.gss_strict_acceptor) {
-		gss_create_empty_oid_set(&status, &oidset);
+		if (gss_create_empty_oid_set(&status, &oidset) == GSS_S_FAILURE) // fix CodeQL SM02313
+		{
+			error("ssh_gssapi_acquire_cred: gss_create_empty_oid_set failed");
+			return (-1);
+		}
 		gss_add_oid_set_member(&status, ctx->oid, &oidset);
 
 		if (gethostname(lname, MAXHOSTNAMELEN)) {
@@ -150,15 +154,20 @@ ssh_gssapi_supported_oids(gss_OID_set *oidset)
 	gss_OID_set supported;
 
 	gss_create_empty_oid_set(&min_status, oidset);
-	gss_indicate_mechs(&min_status, &supported);
-
+	if (gss_indicate_mechs(&min_status, &supported) == GSS_S_FAILURE) // fix CodeQL SM02313
+	{
+		error("ssh_gssapi_supported_oids: gss_indicate_mechs failed to \
+			determine which underlying security mechanisms are available");
+		return;
+	}
+	
 	while (supported_mechs[i]->name != NULL) {
 		if (GSS_ERROR(gss_test_oid_set_member(&min_status,
-		    &supported_mechs[i]->oid, supported, &present)))
+			&supported_mechs[i]->oid, supported, &present)))
 			present = 0;
 		if (present)
 			gss_add_oid_set_member(&min_status,
-			    &supported_mechs[i]->oid, oidset);
+				&supported_mechs[i]->oid, oidset);
 		i++;
 	}
 
diff --git a/kex.c b/kex.c
index f9bf5a223..4010d7cf5 100644
--- a/kex.c
+++ b/kex.c
@@ -606,6 +606,10 @@ kex_input_kexinit(int type, u_int32_t seq, struct ssh *ssh)
 	}
 	ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, NULL);
 	ptr = sshpkt_ptr(ssh, &dlen);
+	if (ptr == NULL) { // fix CodeQL SM02313
+		error_f("kex packet pointer failure");
+		return SSH_ERR_INTERNAL_ERROR;
+	}
 	if ((r = sshbuf_put(kex->peer, ptr, dlen)) != 0)
 		return r;
 
diff --git a/kexc25519.c b/kexc25519.c
index f13d766d7..44cd1ff3f 100644
--- a/kexc25519.c
+++ b/kexc25519.c
@@ -129,6 +129,10 @@ kex_c25519_enc(struct kex *kex, const struct sshbuf *client_blob,
 		goto out;
 	}
 	client_pub = sshbuf_ptr(client_blob);
+	if (client_pub == NULL) { // fix CodeQL SM02313
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
 #ifdef DEBUG_KEXECDH
 	dump_digest("client public key 25519:", client_pub, CURVE25519_SIZE);
 #endif
@@ -185,7 +189,7 @@ kex_c25519_dec(struct kex *kex, const struct sshbuf *server_blob,
 		r = SSH_ERR_ALLOC_FAIL;
 		goto out;
 	}
-	if ((r = kexc25519_shared_key_ext(kex->c25519_client_key, server_pub,
+	if ((r = kexc25519_shared_key_ext(kex->c25519_client_key, server_pub, // CodeQL [SM02311]: false positive server_pub will not be null
 	    buf, 0)) < 0)
 		goto out;
 #ifdef DEBUG_KEXECDH
diff --git a/log.c b/log.c
index ddfd72d50..73e6a6bdc 100644
--- a/log.c
+++ b/log.c
@@ -421,7 +421,7 @@ do_log(LogLevel level, int force, const char *suffix, const char *fmt,
 		closelog_r(&sdata);
 #else
 		openlog(progname, LOG_PID, log_facility);
-		syslog(pri, "%.500s", fmtbuf);
+		syslog(pri, "%.500s", fmtbuf); // CodeQL [SM01733] false positive: not a format call
 		closelog();
 #endif
 	}
diff --git a/misc.c b/misc.c
index 874e9e412..b2bee4e23 100644
--- a/misc.c
+++ b/misc.c
@@ -1151,7 +1151,7 @@ freeargs(arglist *args)
 
 #ifdef WINDOWS
 void
-duplicateargs(arglist *dest, arglist *source)
+duplicateargs(arglist *dest, const arglist *source)
 {
 	if (!source || !dest)
 		return;
@@ -1886,7 +1886,7 @@ parse_ipqos(const char *cp)
 			return ipqos[i].value;
 	}
 	/* Try parsing as an integer */
-	val = strtol(cp, &ep, 0);
+	val = strtol(cp, &ep, 0); // CodeQL [SM02313]: strtoul will initialize ep
 	if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255)
 		return -1;
 	return val;
@@ -2272,7 +2272,7 @@ safe_path(const char *name, struct stat *stp, const char *pw_dir,
 		}
 
 		/* If are past the homedir then we can stop */
-		if (comparehome && strcmp(homedir, buf) == 0)
+		if (comparehome && strcmp(homedir, buf) == 0) // CodeQL [SM01714] false positive: homedir is null terminated
 			break;
 
 		/*
diff --git a/misc.h b/misc.h
index 5683422ed..6bf4494b1 100644
--- a/misc.h
+++ b/misc.h
@@ -124,7 +124,7 @@ void	 replacearg(arglist *, u_int, char *, ...)
 	    __attribute__((format(printf, 3, 4)));
 void	 freeargs(arglist *);
 #ifdef WINDOWS
-void	 duplicateargs(arglist *, arglist *);
+void	 duplicateargs(arglist *, const arglist *);
 #endif
 
 int	 tun_open(int, int, char **);
diff --git a/monitor.c b/monitor.c
index f1f7605d0..51ab6d6c3 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1319,13 +1319,13 @@ monitor_valid_userblob(struct ssh *ssh, const u_char *data, u_int datalen)
 	if ((r = sshbuf_skip_string(b)) != 0 ||	/* service */
 	    (r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
 		fatal_fr(r, "parse method");
-	if (strcmp("publickey", cp) != 0) {
-		if (strcmp("publickey-hostbound-v00@openssh.com", cp) == 0)
+	if (strcmp("publickey", cp) != 0) { // CodeQL [SM03650]: false positive cp repopulated in previous line
+		if (strcmp("publickey-hostbound-v00@openssh.com", cp) == 0) // CodeQL [SM03650]: false positive cp repopulated in previous line
 			hostbound = 1;
 		else
 			fail++;
 	}
-	free(cp);
+	free(cp); // CodeQL [SM03650]: false positive cp repopulated in previous line
 	if ((r = sshbuf_get_u8(b, &type)) != 0)
 		fatal_fr(r, "parse pktype");
 	if (type == 0)
@@ -1390,9 +1390,9 @@ monitor_valid_hostbasedblob(const u_char *data, u_int datalen,
 	if ((r = sshbuf_skip_string(b)) != 0 ||	/* service */
 	    (r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
 		fatal_fr(r, "parse method");
-	if (strcmp(cp, "hostbased") != 0)
+	if (strcmp(cp, "hostbased") != 0) // CodeQL [SM01977]: false positive cp has not been previously freed, CodeQL [SM03650]: false positive cp has not been previously freed
 		fail++;
-	free(cp);
+	free(cp); // CodeQL [SM03650]: false positive cp populated again in line 1394
 	if ((r = sshbuf_skip_string(b)) != 0 ||	/* pkalg */
 	    (r = sshbuf_skip_string(b)) != 0)	/* pkblob */
 		fatal_fr(r, "parse pk");
diff --git a/monitor_wrap.c b/monitor_wrap.c
index bbe41c106..7b98c7372 100644
--- a/monitor_wrap.c
+++ b/monitor_wrap.c
@@ -618,7 +618,7 @@ mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
 	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
 	free(p);
 
-	if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0)
+	if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0) // CodeQL [SM01714] false positive: sshbuf_get_cstring null terminates msg
 		fatal_fr(r, "put loginmsg");
 	free(msg);
 
diff --git a/openbsd-compat/base64.c b/openbsd-compat/base64.c
index e5faba3c5..a6b16e5c8 100644
--- a/openbsd-compat/base64.c
+++ b/openbsd-compat/base64.c
@@ -135,7 +135,7 @@ b64_ntop(u_char const *src, size_t srclength, char *target, size_t targsize)
 	size_t datalength = 0;
 	u_char input[3];
 	u_char output[4];
-	u_int i;
+	size_t i; // fix CodeQL SM01735
 
 	while (2 < srclength) {
 		input[0] = *src++;
diff --git a/openbsd-compat/getopt_long.c b/openbsd-compat/getopt_long.c
index 1a5001f7d..4af43e0f4 100644
--- a/openbsd-compat/getopt_long.c
+++ b/openbsd-compat/getopt_long.c
@@ -346,7 +346,7 @@ start:
 			return (-1);
 		}
 		if (*(place = nargv[optind]) != '-' ||
-		    (place[1] == '\0' && strchr(options, '-') == NULL)) {
+		    (place[1] == '\0' && strchr(options, '-') == NULL)) { // CodeQL [SM01947]: upstream code; place re-assigned in previous line
 			place = EMSG;		/* found non-option */
 			if (flags & FLAG_ALLARGS) {
 				/*
diff --git a/openbsd-compat/glob.c b/openbsd-compat/glob.c
index e89151789..fe33ca8b8 100644
--- a/openbsd-compat/glob.c
+++ b/openbsd-compat/glob.c
@@ -536,7 +536,7 @@ glob0(const Char *pattern, glob_t *pglob, struct glob_lim *limitp)
 			/* collapse adjacent stars to one,
 			 * to avoid exponential behavior
 			 */
-			if (bufnext == patbuf || bufnext[-1] != M_ALL)
+			if (bufnext == patbuf || bufnext[-1] != M_ALL) // CodeQL [SM01947]: false positive bufnext is more than 1 byte
 				*bufnext++ = M_ALL;
 			break;
 		default:
diff --git a/openbsd-compat/strtonum.c b/openbsd-compat/strtonum.c
index 130d89684..e7cb0ab37 100644
--- a/openbsd-compat/strtonum.c
+++ b/openbsd-compat/strtonum.c
@@ -52,7 +52,7 @@ strtonum(const char *numstr, long long minval, long long maxval,
 	if (minval > maxval)
 		error = INVALID;
 	else {
-		ll = strtoll(numstr, &ep, 10);
+		ll = strtoll(numstr, &ep, 10); // CodeQL [SM02313]: strtoll will initialize ep
 		if (numstr == ep || *ep != '\0')
 			error = INVALID;
 		else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval)
diff --git a/packet.c b/packet.c
index 3f64d2d32..00b4996ab 100644
--- a/packet.c
+++ b/packet.c
@@ -2633,6 +2633,8 @@ ssh_packet_send_mux(struct ssh *ssh)
 	if (len < 6)
 		return SSH_ERR_INTERNAL_ERROR;
 	cp = sshbuf_mutable_ptr(state->outgoing_packet);
+	if (cp == NULL) // fix CodeQL SM02313
+		return SSH_ERR_INTERNAL_ERROR;
 	type = cp[5];
 	if (ssh_packet_log_type(type))
 		debug3_f("type %u", type);
diff --git a/readconf.c b/readconf.c
index 7ba207cdc..0cfc3d2ca 100644
--- a/readconf.c
+++ b/readconf.c
@@ -948,13 +948,13 @@ process_config_line_depth(Options *options, struct passwd *pw, const char *host,
 {
 	char *str, **charptr, *endofnumber, *keyword, *arg, *arg2, *p;
 	char **cpptr, ***cppptr, fwdarg[256];
-	u_int i, *uintptr, uvalue, max_entries = 0;
+	u_int *uintptr, uvalue, max_entries = 0;
 	int r, oactive, negated, opcode, *intptr, value, value2, cmdline = 0;
 	int remotefwd, dynamicfwd;
 	LogLevel *log_level_ptr;
 	SyslogFacility *log_facility_ptr;
 	long long val64;
-	size_t len;
+	size_t len, i; // fix CodeQL SM01735
 	struct Forward fwd;
 	const struct multistate *multistate_ptr;
 	struct allowed_cname *cname;
@@ -2081,7 +2081,7 @@ parse_pubkey_algos:
 			goto out;
 		}
 		/* Parse mode in octal format */
-		value = strtol(arg, &endofnumber, 8);
+		value = strtol(arg, &endofnumber, 8); // CodeQL [SM02313]: strtol initializes endofnumber
 		if (arg == endofnumber || value < 0 || value > 0777) {
 			error("%.200s line %d: Bad mask.", filename, linenum);
 			goto out;
diff --git a/regress/unittests/test_helper/fuzz.c b/regress/unittests/test_helper/fuzz.c
index 78b36654d..982e283ef 100644
--- a/regress/unittests/test_helper/fuzz.c
+++ b/regress/unittests/test_helper/fuzz.c
@@ -160,7 +160,7 @@ dump(u_char *p, size_t len)
 	size_t i, j;
 
 	for (i = 0; i < len; i += 16) {
-		fprintf(stderr, "%.4zd: ", i);
+		fprintf(stderr, "%.4zu: ", i); // fix CodeQL SM01735
 		for (j = i; j < i + 16; j++) {
 			if (j < len)
 				fprintf(stderr, "%02x ", p[j]);
@@ -218,7 +218,7 @@ fuzz_begin(u_int strategies, const void *p, size_t l)
 
 	assert(p != NULL);
 	assert(ret != NULL);
-	ret->seed = malloc(l);
+	ret->seed = malloc(l); // CodeQL [SM02311]: tests rely on assert for NULL checks
 	assert(ret->seed != NULL);
 	memcpy(ret->seed, p, l);
 	ret->slen = l;
diff --git a/regress/unittests/test_helper/test_helper.c b/regress/unittests/test_helper/test_helper.c
index 0f396edb2..5d330e380 100644
--- a/regress/unittests/test_helper/test_helper.c
+++ b/regress/unittests/test_helper/test_helper.c
@@ -159,7 +159,7 @@ main(int argc, char **argv)
 	/* Handle systems without __progname */
 	if (__progname == NULL) {
 		__progname = strrchr(argv[0], '/');
-		if (__progname == NULL || __progname[1] == '\0')
+		if (__progname == NULL || (__progname[0] != '\0' && __progname[1] == '\0')) // fix CodeQL SM01947
 			__progname = argv[0];	
 		else
 			__progname++;
@@ -420,7 +420,7 @@ tohex(const void *_s, size_t l)
 
 	assert(r != NULL);
 	for (i = j = 0; i < l; i++) {
-		r[j++] = hex[(s[i] >> 4) & 0xf];
+		r[j++] = hex[(s[i] >> 4) & 0xf]; // CodeQL [SM02311]: tests rely on assert for NULL checks
 		r[j++] = hex[s[i] & 0xf];
 	}
 	r[j] = '\0';
diff --git a/regress/unittests/win32compat/file_tests.c b/regress/unittests/win32compat/file_tests.c
index f0c4c6d3b..10ac9a63c 100644
--- a/regress/unittests/win32compat/file_tests.c
+++ b/regress/unittests/win32compat/file_tests.c
@@ -193,6 +193,7 @@ void file_simple_fileio()
 		retValue = lseek(f, offset, SEEK_SET);
 		ASSERT_INT_EQ(retValue, 0);
 		char *tmp = dup_str(small_read_buf);
+		ASSERT_PTR_NE(tmp, NULL);
 
 		retValue = read(f, small_read_buf, SMALL_RECV_BUF_SIZE);
 		small_read_buf[retValue] = '\0';
@@ -419,6 +420,8 @@ file_miscellaneous_tests()
 	ASSERT_INT_NE(retValue, -1);
 
 	char *tmp = dup_str(thishost);
+	if (tmp == NULL)
+		goto out;
 	int len = strlen(tmp);
 
 	int f = dup(STDOUT_FILENO);
@@ -486,7 +489,7 @@ file_miscellaneous_tests()
 	close(f);
 	retValue = unlink(tmp_filename);
 	ASSERT_INT_EQ(retValue, 0);	
-
+out:
 	TEST_DONE();
 }
 
diff --git a/regress/unittests/win32compat/miscellaneous_tests.c b/regress/unittests/win32compat/miscellaneous_tests.c
index 305ab410f..536e2a75e 100644
--- a/regress/unittests/win32compat/miscellaneous_tests.c
+++ b/regress/unittests/win32compat/miscellaneous_tests.c
@@ -37,8 +37,12 @@ test_path_conversion_utilities()
 
 	char *s = "c:\\testdir\\test";
 	char *windows_style_path = dup_str(s);
+	if (windows_style_path == NULL)
+		goto out;
 	int len = strlen(windows_style_path);
 	char *backup = malloc(len + 1);
+	if (backup == NULL)
+		goto out;
 	strncpy(backup, windows_style_path, len);
 	backup[len] = '\0';
 
@@ -53,8 +57,9 @@ test_path_conversion_utilities()
 
 	retValue = strcmp(windows_style_path, backup);
 	ASSERT_INT_EQ(retValue, 0);
-
-	free(windows_style_path);
+out:
+	if (windows_style_path)
+		free(windows_style_path);
 
 	TEST_DONE();
 }
@@ -80,6 +85,8 @@ test_sanitizedpath()
 
 	size_t win32prgdir_len = strlen(win32prgdir_utf8);
 	char *tmp_path = malloc(win32prgdir_len + 2); /* 1-NULL and 1-adding "/" */
+	if (tmp_path == NULL)
+		goto out;
 	tmp_path[0] = '/';
 	strcpy(tmp_path+1, win32prgdir_utf8);
 	tmp_path[win32prgdir_len+1] = '\0';
@@ -101,7 +108,7 @@ test_sanitizedpath()
 	retValue = wcscmp(ret, s2);
 	ASSERT_INT_EQ(retValue, 0);
 	free(ret);
-
+out:
 	free(win32prgdir);
 
 	TEST_DONE();
@@ -118,9 +125,10 @@ test_pw()
 
 	struct passwd *pw1 = NULL;
 	char *user = dup_str(pw->pw_name);
-	pw1 = getpwnam(user);
-	ASSERT_PTR_NE(pw1, NULL);
-
+	if (user != NULL) {
+		pw1 = getpwnam(user);
+		ASSERT_PTR_NE(pw1, NULL);
+	}
 	TEST_DONE();
 }
 
diff --git a/regress/unittests/win32compat/signal_tests.c b/regress/unittests/win32compat/signal_tests.c
index d05dd8c97..d6fd492d2 100644
--- a/regress/unittests/win32compat/signal_tests.c
+++ b/regress/unittests/win32compat/signal_tests.c
@@ -44,7 +44,7 @@ VOID TEST_RESOURCES(BOOL start)
 	static DWORD initial_count = 0;
 	if (start) GetProcessHandleCount(GetCurrentProcess(), &initial_count);
 	else {
-		DWORD final_count;
+		DWORD final_count = 0;
 		GetProcessHandleCount(GetCurrentProcess(), &final_count);
 		ASSERT_INT_EQ(initial_count, final_count);
 	}
diff --git a/regress/unittests/win32compat/tests.c b/regress/unittests/win32compat/tests.c
index 5d8374ae4..018e155e6 100644
--- a/regress/unittests/win32compat/tests.c
+++ b/regress/unittests/win32compat/tests.c
@@ -50,6 +50,8 @@ delete_dir_recursive(char *full_dir_path)
 	struct dirent *dp;
 	char mode[12];
 	char *tmpFullPath = malloc(PATH_MAX + 1);
+	if (NULL == tmpFullPath) return;
+
 	strcpy(tmpFullPath, full_dir_path);
 	int tmpStrLen = strlen(tmpFullPath);
 	tmpFullPath[tmpStrLen++] = '\\';
diff --git a/servconf.c b/servconf.c
index eb086103b..359634f36 100644
--- a/servconf.c
+++ b/servconf.c
@@ -2403,7 +2403,7 @@ process_server_config_line_depth(ServerOptions *options, char *line,
 			fatal("%s line %d: %s missing argument.",
 			    filename, linenum, keyword);
 		/* Parse mode in octal format */
-		value = strtol(arg, &p, 8);
+		value = strtol(arg, &p, 8); // CodeQL [SM02313]: strtol will initialize p
 		if (arg == p || value < 0 || value > 0777)
 			fatal("%s line %d: Invalid %s.",
 			    filename, linenum, keyword);
diff --git a/sftp-client.c b/sftp-client.c
index ef3040ee9..b73f770ac 100644
--- a/sftp-client.c
+++ b/sftp-client.c
@@ -505,35 +505,35 @@ do_init(int fd_in, int fd_out, u_int transfer_buflen, u_int num_requests,
 		    (r = sshbuf_get_string(msg, &value, &vlen)) != 0)
 			fatal_fr(r, "parse extension");
 		if (strcmp(name, "posix-rename@openssh.com") == 0 &&
-		    strcmp((char *)value, "1") == 0) {
+		    strcmp((char *)value, "1") == 0) { // CodeQL [SM01714] false positive: value is null terminated
 			ret->exts |= SFTP_EXT_POSIX_RENAME;
 			known = 1;
 		} else if (strcmp(name, "statvfs@openssh.com") == 0 &&
-		    strcmp((char *)value, "2") == 0) {
+		    strcmp((char *)value, "2") == 0) { // CodeQL [SM03650] false positive: value has not been previously freed
 			ret->exts |= SFTP_EXT_STATVFS;
 			known = 1;
 		} else if (strcmp(name, "fstatvfs@openssh.com") == 0 &&
-		    strcmp((char *)value, "2") == 0) {
+		    strcmp((char *)value, "2") == 0) { // CodeQL [SM03650] false positive: value has not been previously freed
 			ret->exts |= SFTP_EXT_FSTATVFS;
 			known = 1;
 		} else if (strcmp(name, "hardlink@openssh.com") == 0 &&
-		    strcmp((char *)value, "1") == 0) {
+		    strcmp((char *)value, "1") == 0) { // CodeQL [SM03650] false positive: value has not been previously freed
 			ret->exts |= SFTP_EXT_HARDLINK;
 			known = 1;
 		} else if (strcmp(name, "fsync@openssh.com") == 0 &&
-		    strcmp((char *)value, "1") == 0) {
+		    strcmp((char *)value, "1") == 0) { // CodeQL [SM03650] false positive: value has not been previously freed
 			ret->exts |= SFTP_EXT_FSYNC;
 			known = 1;
 		} else if (strcmp(name, "lsetstat@openssh.com") == 0 &&
-		    strcmp((char *)value, "1") == 0) {
+		    strcmp((char *)value, "1") == 0) { // CodeQL [SM03650] false positive: value has not been previously freed
 			ret->exts |= SFTP_EXT_LSETSTAT;
 			known = 1;
 		} else if (strcmp(name, "limits@openssh.com") == 0 &&
-		    strcmp((char *)value, "1") == 0) {
+		    strcmp((char *)value, "1") == 0) { // CodeQL [SM03650] false positive: value has not been previously freed
 			ret->exts |= SFTP_EXT_LIMITS;
 			known = 1;
 		} else if (strcmp(name, "expand-path@openssh.com") == 0 &&
-		    strcmp((char *)value, "1") == 0) {
+		    strcmp((char *)value, "1") == 0) { // CodeQL [SM03650] false positive: value has not been previously freed
 			ret->exts |= SFTP_EXT_PATH_EXPAND;
 			known = 1;
 		} else if (strcmp(name, "copy-data") == 0 &&
@@ -548,12 +548,12 @@ do_init(int fd_in, int fd_out, u_int transfer_buflen, u_int num_requests,
 		}
 		if (known) {
 			debug2("Server supports extension \"%s\" revision %s",
-			    name, value);
+			    name, value); // CodeQL [SM03650] false positive: value has not been previously freed
 		} else {
 			debug2("Unrecognised server extension \"%s\"", name);
 		}
 		free(name);
-		free(value);
+		free(value); // CodeQL [SM03650] false positive: value has not been previously freed
 	}
 
 	sshbuf_free(msg);
@@ -782,12 +782,12 @@ do_lsreaddir(struct sftp_conn *conn, const char *path, int print_flag,
 			if ((r = decode_attrib(msg, &a)) != 0) {
 				error_fr(r, "couldn't decode attrib");
 				free(filename);
-				free(longname);
+				free(longname); // CodeQL [SM01977]: false positive longname has not been previously freed, CodeQL [SM03650]: false positive longname has not been previously freed
 				goto out;
 			}
 
 			if (print_flag)
-				mprintf("%s\n", longname);
+				mprintf("%s\n", longname); // CodeQL[SM03650]: false positive longname has not been previously freed
 
 			/*
 			 * Directory entries should never contain '/'
@@ -801,12 +801,12 @@ do_lsreaddir(struct sftp_conn *conn, const char *path, int print_flag,
 				*dir = xreallocarray(*dir, ents + 2, sizeof(**dir));
 				(*dir)[ents] = xcalloc(1, sizeof(***dir));
 				(*dir)[ents]->filename = xstrdup(filename);
-				(*dir)[ents]->longname = xstrdup(longname);
+				(*dir)[ents]->longname = xstrdup(longname); // CodeQL [SM03650]: false positive longname has not been previously freed
 				memcpy(&(*dir)[ents]->a, &a, sizeof(a));
 				(*dir)[++ents] = NULL;
 			}
 			free(filename);
-			free(longname);
+			free(longname); // CodeQL [SM03650]: false positive longname has not been previously freed
 		}
 	}
 	status = 0;
diff --git a/sftp-server.c b/sftp-server.c
index b93a2980b..a32927365 100644
--- a/sftp-server.c
+++ b/sftp-server.c
@@ -1082,13 +1082,13 @@ process_fsetstat(u_int32_t id)
 
 		if (a.flags & SSH2_FILEXFER_ATTR_SIZE) {
 			logit("set \"%s\" size %llu",
-			    name, (unsigned long long)a.size);
+			    name, (unsigned long long)a.size); // CodeQL [SM02311]: false positive name will not be null because of handle_to_fd check
 			r = ftruncate(fd, a.size);
 			if (r == -1)
 				status = errno_to_portable(errno);
 		}
 		if (a.flags & SSH2_FILEXFER_ATTR_PERMISSIONS) {
-			logit("set \"%s\" mode %04o", name, a.perm);
+			logit("set \"%s\" mode %04o", name, a.perm); // CodeQL [SM02311]: false positive name will not be null because of handle_to_fd check
 #ifdef HAVE_FCHMOD
 			r = fchmod(fd, a.perm & 07777);
 #else
@@ -1103,7 +1103,7 @@ process_fsetstat(u_int32_t id)
 
 			strftime(buf, sizeof(buf), "%Y%m%d-%H:%M:%S",
 			    localtime(&t));
-			logit("set \"%s\" modtime %s", name, buf);
+			logit("set \"%s\" modtime %s", name, buf); // CodeQL [SM02311]: false positive name will not be null because of handle_to_fd check
 #ifdef HAVE_FUTIMES
 			r = futimes(fd, attrib_to_tv(&a));
 #else
@@ -1113,7 +1113,7 @@ process_fsetstat(u_int32_t id)
 				status = errno_to_portable(errno);
 		}
 		if (a.flags & SSH2_FILEXFER_ATTR_UIDGID) {
-			logit("set \"%s\" owner %lu group %lu", name,
+			logit("set \"%s\" owner %lu group %lu", name, // CodeQL [SM02311]: false positive name will not be null because of handle_to_fd check
 			    (u_long)a.uid, (u_long)a.gid);
 #ifdef HAVE_FCHOWN
 			r = fchown(fd, a.uid, a.gid);
diff --git a/sftp.c b/sftp.c
index ded20d372..63bb7e39c 100644
--- a/sftp.c
+++ b/sftp.c
@@ -344,13 +344,15 @@ local_do_shell(const char *args)
 			if (cygwin_path_prefix_start = strstr(args, CYGWIN_PATH_PREFIX)) {
 				int len = strlen(cygwin_path_prefix_start) + 1;
 				char *tmp = malloc(len);
-				memset(tmp, 0, len);
+				if (tmp != NULL) // fix CodeQL SM02313
+				{
+					memset(tmp, 0, len);
 
-				bash_to_win_path(cygwin_path_prefix_start, tmp, len);
-				strcpy_s(cygwin_path_prefix_start, len, tmp); /* override the original string */
+					bash_to_win_path(cygwin_path_prefix_start, tmp, len);
+					strcpy_s(cygwin_path_prefix_start, len, tmp); /* override the original string */
 
-				if (tmp)
 					free(tmp);
+				}
 			}
 		}
 
@@ -1050,6 +1052,10 @@ do_globbed_ls(struct sftp_conn *conn, const char *path,
 	for (nentries = 0; g.gl_pathv[nentries] != NULL; nentries++)
 		;	/* count entries */
 	indices = calloc(nentries, sizeof(*indices));
+	if (indices == NULL) // fix CodeQL SM02313
+	{
+		return -1;
+	}
 	for (i = 0; i < nentries; i++)
 		indices[i] = i;
 
@@ -1531,7 +1537,7 @@ parse_args(const char **cpp, int *ignore_errors, int *disable_echo, int *aflag,
 		if (argc - optidx < 1)
 			goto need_num_arg;
 		errno = 0;
-		ll = strtoll(argv[optidx], &cp2, base);
+		ll = strtoll(argv[optidx], &cp2, base); // CodeQL [SM02313]: strtoll will initialize cp2
 		if (cp2 == argv[optidx] || *cp2 != '\0' ||
 		    ((ll == LLONG_MIN || ll == LLONG_MAX) && errno == ERANGE) ||
 		    ll < 0 || ll > UINT32_MAX) {
diff --git a/ssh-ed25519-sk.c b/ssh-ed25519-sk.c
index 4393ca669..75a2731f5 100644
--- a/ssh-ed25519-sk.c
+++ b/ssh-ed25519-sk.c
@@ -133,7 +133,7 @@ ssh_ed25519_sk_verify(const struct sshkey *key,
 	sm = sshbuf_ptr(encoded);
 	smlen = sshbuf_len(encoded);
 	mlen = smlen;
-	if ((m = malloc(smlen)) == NULL) {
+	if (sm == NULL || (m = malloc(smlen)) == NULL) { // fix CodeQL SM02313
 		r = SSH_ERR_ALLOC_FAIL;
 		goto out;
 	}
diff --git a/ssh-keygen.c b/ssh-keygen.c
index 0fe1d7bff..99ca66c99 100644
--- a/ssh-keygen.c
+++ b/ssh-keygen.c
@@ -1544,7 +1544,7 @@ do_change_comment(struct passwd *pw, const char *identity_comment)
 	    private_key_format != SSHKEY_PRIVATE_OPENSSH) {
 		error("Comments are only supported for keys stored in "
 		    "the new format (-o).");
-		explicit_bzero(passphrase, strlen(passphrase));
+		explicit_bzero(passphrase, strlen(passphrase)); // CodeQL [SM01714] false positive: passphrase is null terminated
 		sshkey_free(private);
 		exit(1);
 	}
diff --git a/ssh-pkcs11-client.c b/ssh-pkcs11-client.c
index fb7ab3923..4f29168d0 100644
--- a/ssh-pkcs11-client.c
+++ b/ssh-pkcs11-client.c
@@ -561,7 +561,7 @@ pkcs11_add_provider(char *name, char *pin, struct sshkey ***keysp,
 			if (labelsp)
 				(*labelsp)[i] = label;
 			else
-				free(label);
+				free(label); // CodeQL [SM03650]: false positive label not previously freed
 			free(blob);
 		}
 	} else if (type == SSH2_AGENT_FAILURE) {
diff --git a/ssh-sk.c b/ssh-sk.c
index fbeb39320..c635a933a 100644
--- a/ssh-sk.c
+++ b/ssh-sk.c
@@ -521,6 +521,8 @@ sshsk_enroll(int type, const char *provider_path, const char *device,
 		goto out;
 	} else {
 		challenge = sshbuf_ptr(challenge_buf);
+		if (challenge == NULL) // fix CodeQL SM02313
+			goto out;
 		challenge_len = sshbuf_len(challenge_buf);
 		debug3_f("using explicit challenge len=%zd", challenge_len);
 	}
diff --git a/ssh_api.c b/ssh_api.c
index d3c661761..6ae451ca1 100644
--- a/ssh_api.c
+++ b/ssh_api.c
@@ -332,6 +332,9 @@ _ssh_read_banner(struct ssh *ssh, struct sshbuf *banner)
 	int r = 0, remote_major, remote_minor, expect_nl;
 	size_t n, j;
 
+	if (s == NULL) // fix CodeQL SM02313
+		return SSH_ERR_INTERNAL_ERROR;
+
 	for (j = n = 0;;) {
 		sshbuf_reset(banner);
 		expect_nl = 0;
diff --git a/sshbuf-getput-basic.c b/sshbuf-getput-basic.c
index 5c71b0e53..78db4b700 100644
--- a/sshbuf-getput-basic.c
+++ b/sshbuf-getput-basic.c
@@ -39,6 +39,8 @@ sshbuf_get(struct sshbuf *buf, void *v, size_t len)
 
 	if ((r = sshbuf_consume(buf, len)) < 0)
 		return r;
+	if (p == NULL) // fix CodeQL SM02313
+		return SSH_ERR_INTERNAL_ERROR;
 	if (v != NULL && len != 0)
 		memcpy(v, p, len);
 	return 0;
@@ -49,11 +51,13 @@ sshbuf_get_u64(struct sshbuf *buf, u_int64_t *valp)
 {
 	const u_char *p = sshbuf_ptr(buf);
 	int r;
-
 	if ((r = sshbuf_consume(buf, 8)) < 0)
 		return r;
-	if (valp != NULL)
+	if (valp != NULL) {
+		if (p == NULL) // fix CodeQL SM02313
+			return SSH_ERR_INTERNAL_ERROR;
 		*valp = PEEK_U64(p);
+	}
 	return 0;
 }
 
@@ -65,8 +69,11 @@ sshbuf_get_u32(struct sshbuf *buf, u_int32_t *valp)
 
 	if ((r = sshbuf_consume(buf, 4)) < 0)
 		return r;
-	if (valp != NULL)
+	if (valp != NULL) {
+		if (p == NULL) // fix CodeQL SM02313
+			return SSH_ERR_INTERNAL_ERROR;
 		*valp = PEEK_U32(p);
+	}
 	return 0;
 }
 
@@ -78,8 +85,11 @@ sshbuf_get_u16(struct sshbuf *buf, u_int16_t *valp)
 
 	if ((r = sshbuf_consume(buf, 2)) < 0)
 		return r;
-	if (valp != NULL)
+	if (valp != NULL) {
+		if (p == NULL) // fix CodeQL SM02313
+			return SSH_ERR_INTERNAL_ERROR;
 		*valp = PEEK_U16(p);
+	}
 	return 0;
 }
 
@@ -91,8 +101,11 @@ sshbuf_get_u8(struct sshbuf *buf, u_char *valp)
 
 	if ((r = sshbuf_consume(buf, 1)) < 0)
 		return r;
-	if (valp != NULL)
+	if (valp != NULL) {
+		if (p == NULL) // fix CodeQL SM02313
+			return SSH_ERR_INTERNAL_ERROR;
 		*valp = (u_int8_t)*p;
+	}
 	return 0;
 }
 
@@ -251,6 +264,8 @@ sshbuf_peek_string_direct(const struct sshbuf *buf, const u_char **valp,
 		SSHBUF_DBG(("SSH_ERR_MESSAGE_INCOMPLETE"));
 		return SSH_ERR_MESSAGE_INCOMPLETE;
 	}
+	if (p == NULL) // fix CodeQL SM02313
+		return SSH_ERR_INTERNAL_ERROR;
 	len = PEEK_U32(p);
 	if (len > SSHBUF_SIZE_MAX - 4) {
 		SSHBUF_DBG(("SSH_ERR_STRING_TOO_LARGE"));
diff --git a/sshbuf-misc.c b/sshbuf-misc.c
index 9c5c42bba..501dfb7fb 100644
--- a/sshbuf-misc.c
+++ b/sshbuf-misc.c
@@ -80,7 +80,7 @@ sshbuf_dtob16(struct sshbuf *buf)
 
 	if (len == 0)
 		return strdup("");
-	if (SIZE_MAX / 2 <= len || (ret = malloc(len * 2 + 1)) == NULL)
+	if (p == NULL || SIZE_MAX / 2 <= len || (ret = malloc(len * 2 + 1)) == NULL) // fix CodeQL SM02313
 		return NULL;
 	for (i = j = 0; i < len; i++) {
 		ret[j++] = hex[(p[i] >> 4) & 0xf];
diff --git a/sshconnect2.c b/sshconnect2.c
index 3607aac58..1fa4de623 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -349,7 +349,7 @@ struct cauthctxt {
 #ifdef GSSAPI
 	/* gssapi */
 	gss_OID_set gss_supported_mechs;
-	u_int mech_tried;
+	size_t mech_tried; // fix CodeQL SM01735
 #endif
 	/* pubkey */
 	struct idlist keys;
diff --git a/sshkey.c b/sshkey.c
index 15f4c8029..ac732807a 100644
--- a/sshkey.c
+++ b/sshkey.c
@@ -4118,6 +4118,10 @@ private2_uudecode(struct sshbuf *blob, struct sshbuf **decodedp)
 
 	/* check preamble */
 	cp = sshbuf_ptr(blob);
+	if (cp == NULL) { // fix CodeQL SM02313
+		r = SSH_ERR_INTERNAL_ERROR;
+		goto out;
+	}
 	encoded_len = sshbuf_len(blob);
 	
 #ifdef SUPPORT_CRLF