diff --git a/lib/x509/verify.c b/lib/x509/verify.c
index cb8289e..86a901e 100644
--- a/lib/x509/verify.c
+++ b/lib/x509/verify.c
@@ -674,7 +674,10 @@ _gnutls_x509_verify_certificate (const gnutls_x509_crt_t * certificate_list,
        * certificates can exist in a supplied chain.
        */
       if (!(flags & GNUTLS_VERIFY_ALLOW_ANY_X509_V1_CA_CRT))
-        flags &= ~(GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT);
+        {
+          flags &= ~(GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT);
+          flags |= GNUTLS_VERIFY_DO_NOT_ALLOW_X509_V1_CA_CRT;
+        }
       if ((ret =
            _gnutls_verify_certificate2 (certificate_list[i - 1],
                                         &certificate_list[i], 1, flags,