Vulnerability Note VU#337585

Pubcookie is a software package that provides intra-institutional single-sign-on authentication for end-users over the web. The Pubcookie development team has discovered several cross-site scripting vulnerabilities in the Pubcookie login server's compiled binary "index.cgi" CGI program. Because of flaws in the way the CGI program handles untrusted user-supplied data when printing responses to the browser, an attacker may be able to supply crafted requests containing script or HTML. By luring an unsuspecting user to view the staged content, an attacker can redirect the user to a vulnerable Pubcookie login page and gain access to sensitive information.

An attacker with the ability to inject malicious script may be able to steal sensitive user data including a user's authentication credentials (usernames and passwords), private Pubcookie data including a user's authentication assertion ("granting") cookies, and single sign-on (SSO or "login") session cookies. An attacker injecting HTML tags using the vulnerability may also be able to deface a site's Pubcookie login page for a single instance (viewing) of the page.

Upgrade

The Pubcookie project has released versions 3.3.0a (current production release; Unix and Windows) and 3.2.1b (Unix-only patch release) that contains fixes for this vulnerability.

These releases are available from the project's downloads page. Users running an affected version of the software are encouraged to upgrade to one of the patch releases listed above.