diff --git a/CryptoPkg/Library/BaseCryptLib/Pk/CryptX509.c b/CryptoPkg/Library/BaseCryptLib/Pk/CryptX509.c
index 1182323b63..7ebec9dbad 100644
--- a/CryptoPkg/Library/BaseCryptLib/Pk/CryptX509.c
+++ b/CryptoPkg/Library/BaseCryptLib/Pk/CryptX509.c
@@ -839,17 +839,17 @@ X509GetTBSCert (
   Length = 0;
   Inf    = ASN1_get_object (&Temp, (long *)&Length, (int *)&Asn1Tag, (int *)&ObjClass, (long)CertSize);
 
-  if (((Inf & 0x80) == 0x00) && (Asn1Tag != V_ASN1_SEQUENCE)) {
+  if (((Inf & 0x80) == 0x80) && (Asn1Tag != V_ASN1_SEQUENCE)) {
     return FALSE;
   }
 
   *TBSCert = (UINT8 *)Temp;
 
-  ASN1_get_object (&Temp, (long *)&Length, (int *)&Asn1Tag, (int *)&ObjClass, (long)Length);
+  Inf = ASN1_get_object (&Temp, (long *)&Length, (int *)&Asn1Tag, (int *)&ObjClass, (long)Length);
   //
   // Verify the parsed TBSCertificate is one correct SEQUENCE data.
   //
-  if (((Inf & 0x80) == 0x00) && (Asn1Tag != V_ASN1_SEQUENCE)) {
+  if (((Inf & 0x80) == 0x80) && (Asn1Tag != V_ASN1_SEQUENCE)) {
     return FALSE;
   }