The ocsp_check function in rlm_eap_tls.c in FreeRADIUS 2.1.11, when OCSP is enabled, does not properly parse replies from OCSP responders, which allows remote attackers to bypass authentication by using the EAP-TLS protocol with a revoked X.509 client certificate.
secunia.com/advisories/45425
securityreason.com/securityalert/8325
securitytracker.com/id?1025833
www.openwall.com/lists/oss-security/2011/07/15/6
www.openwall.com/lists/oss-security/2011/07/18/2
www.openwall.com/lists/oss-security/2011/07/20/9
www.securityfocus.com/archive/1/518974/100/0/threaded
www.securityfocus.com/bid/48880
bugzilla.redhat.com/show_bug.cgi?id=724815
exchange.xforce.ibmcloud.com/vulnerabilities/68782
www.dfn-cert.de/informationen/Sicherheitsbulletins/dsb-2011-01.html