The Service Provider (SP) in PicketLink before 2.7.0 does not ensure that it is a member of an Audience element when an AudienceRestriction is specified, which allows remote attackers to log in to other users' accounts via a crafted SAML assertion. NOTE: this identifier has been SPLIT per ADT2 due to different vulnerability types. See CVE-2015-6254 for lack of validation for the Destination attribute in a Response element in a SAML assertion.
https://issues.jboss.org/browse/PLINK-678
https://bugzilla.redhat.com/show_bug.cgi?id=1194832
http://rhn.redhat.com/errata/RHSA-2015-0849.html
http://rhn.redhat.com/errata/RHSA-2015-0848.html