Source:

http://www.gnutls.org/security.html

Info:

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-0092

lib/x509/verify.c in GnuTLS before 3.1.22 and 3.2.x before 3.2.12 does not 

properly handle unspecified errors when verifying X.509 certificates from SSL 

servers, which allows man-in-the-middle attackers to spoof servers via a 

crafted certificate.

Status:

Need to determine if this patch has been sent upstream.

--- gnutls-2.8.6/lib/x509/verify.c.orig	Thu Mar  6 14:01:51 2014

+++ gnutls-2.8.6/lib/x509/verify.c	Thu Mar  6 14:50:52 2014

@@ -112,7 +112,7 @@

   if (result < 0)

     {

       gnutls_assert ();

-      goto cleanup;

+      goto fail;

     }

   result =

@@ -121,7 +121,7 @@

   if (result < 0)

     {

       gnutls_assert ();

-      goto cleanup;

+      goto fail;

     }

   result =

@@ -129,7 +129,7 @@

   if (result < 0)

     {

       gnutls_assert ();

-      goto cleanup;

+      goto fail;

     }

   result =

@@ -137,7 +137,7 @@

   if (result < 0)

     {

       gnutls_assert ();

-      goto cleanup;

+      goto fail;

     }

   /* If the subject certificate is the same as the issuer

@@ -177,6 +177,7 @@

   else

     gnutls_assert ();

+fail:

   result = 0;

 cleanup:

@@ -269,7 +270,7 @@

   gnutls_datum_t cert_signed_data = { NULL, 0 };

   gnutls_datum_t cert_signature = { NULL, 0 };

   gnutls_x509_crt_t issuer;

-  int ret, issuer_version, result;

+  int ret, issuer_version, result = 0;

   if (output)

     *output = 0;

@@ -299,7 +300,7 @@

   if (issuer_version < 0)

     {

       gnutls_assert ();

-      return issuer_version;

+      return 0;

     }

   if (!(flags & GNUTLS_VERIFY_DISABLE_CA_SIGN) &&

@@ -320,6 +321,7 @@

   if (result < 0)

     {

       gnutls_assert ();

+      result = 0;

       goto cleanup;

     }

@@ -328,23 +330,25 @@

   if (result < 0)

     {

       gnutls_assert ();

+      result = 0;

       goto cleanup;

     }

-  ret =

+  result =

     _gnutls_x509_verify_signature (&cert_signed_data, NULL, &cert_signature,

 				   issuer);

-  if (ret < 0)

+  if (result < 0)

     {

+      result = 0;

       gnutls_assert ();

+      goto cleanup;

     }

-  else if (ret == 0)

+  else if (result == 0)

     {

       gnutls_assert ();

       /* error. ignore it */

       if (output)

 	*output |= GNUTLS_CERT_INVALID;

-      ret = 0;

     }

   /* If the certificate is not self signed check if the algorithms

@@ -364,11 +368,10 @@

 	{

 	  if (output)

 	    *output |= GNUTLS_CERT_INSECURE_ALGORITHM | GNUTLS_CERT_INVALID;

-	  ret = 0;

+	  result = 0;

 	}

     }

-  result = ret;

 cleanup:

   _gnutls_free_datum (&cert_signed_data);