Code: int ECDSA_verify(int type, const unsigned char *dgst, int dgst_len,
 		const unsigned char *sigbuf, int sig_len, EC_KEY *eckey)
  	{
 	ECDSA_SIG *s;
 	int ret=-1;
 
 	s = ECDSA_SIG_new();
 	if (s == NULL) return(ret);
	if (d2i_ECDSA_SIG(&s, &sigbuf, sig_len) == NULL) goto err;
 	ret=ECDSA_do_verify(dgst, dgst_len, s, eckey);
 err:
 	ECDSA_SIG_free(s);
 	return(ret);
 	}

Vulnerability Type: 
CWE ID: CWE-310
Summary: OpenSSL before 0.9.8zd, 1.0.0 before 1.0.0p, and 1.0.1 before 1.0.1k does not enforce certain constraints on certificate data, which allows remote attackers to defeat a fingerprint-based certificate-blacklist protection mechanism by including crafted data within a certificate's unsigned portion, related to crypto/asn1/a_verify.c, crypto/dsa/dsa_asn1.c, crypto/ecdsa/ecs_vrf.c, and crypto/x509/x_all.c.
Commit Message: Fix various certificate fingerprint issues.

By using non-DER or invalid encodings outside the signed portion of a
certificate the fingerprint can be changed without breaking the signature.
Although no details of the signed portion of the certificate can be changed
this can cause problems with some applications: e.g. those using the
certificate fingerprint for blacklists.

1. Reject signatures with non zero unused bits.

If the BIT STRING containing the signature has non zero unused bits reject
the signature. All current signature algorithms require zero unused bits.

2. Check certificate algorithm consistency.

Check the AlgorithmIdentifier inside TBS matches the one in the
certificate signature. NB: this will result in signature failure
errors for some broken certificates.

3. Check DSA/ECDSA signatures use DER.

Reencode DSA/ECDSA signatures and compare with the original received
signature. Return an error if there is a mismatch.

This will reject various cases including garbage after signature
(thanks to Antti Karjalainen and Tuomo Untinen from the Codenomicon CROSS
program for discovering this case) and use of BER or invalid ASN.1 INTEGERs
(negative or with leading zeroes).

CVE-2014-8275
Reviewed-by: Emilia Käsper <emilia@openssl.org>