Jasig phpCAS version 1.3.4 is vulnerable to an authentication bypass in the validateCAS20 function when configured to authenticate against an old CAS server.

Apereo Central Authentication Service (CAS) Server before 3.5.3 allows remote attackers to conduct LDAP injection attacks via a crafted username, as demonstrated by using a wildcard and a valid password to bypass LDAP authentication.

phpCAS before 1.3.2 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.

Directory traversal vulnerability in the callback function in client.php in phpCAS before 1.1.3, when proxy mode is enabled, allows remote attackers to create or overwrite arbitrary files via directory traversal sequences in a Proxy Granting Ticket IOU (PGTiou) parameter.

Multiple cross-site scripting (XSS) vulnerabilities in phpCAS before 1.1.3, when proxy mode is enabled, allow remote attackers to inject arbitrary web script or HTML via (1) a crafted Proxy Granting Ticket IOU (PGTiou) parameter to the callback function in client.php, (2) vectors involving functions that make getCallbackURL calls, or (3) vectors involving functions that make getURL calls.

PGTStorage/pgt-file.php in phpCAS before 1.1.3, when proxy mode is enabled, allows local users to overwrite arbitrary files via a symlink attack on an unspecified file.