The _gnutls_x509_verify_certificate function in lib/x509/verify.c in libgnutls in GnuTLS before 2.6.1 trusts certificate chains in which the last certificate is an arbitrary trusted, self-signed certi...

Mozilla Network Security Services (NSS) before 3.12.3, Firefox before 3.0.13, Thunderbird before 2.0.0.23, and SeaMonkey before 1.1.18 do not properly handle a '\0' character in a domain name in the s...

Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middl...

offlineimap before 6.3.2 does not check for SSL server certificate validation when "ssl = yes" option is specified which can allow man-in-the-middle attacks.

The Certificate Trust Policy component in Apple Mac OS X before 10.6.8 does not perform CRL checking for Extended Validation (EV) certificates that lack OCSP URLs, which might allow man-in-the-middle ...

Cisco IronPort Web Security Appliance does not check for certificate revocation which could lead to MITM attacks