SquirrelMail Security Notice ============================ About ----- SquirrelMail is a standards-based webmail package written in PHP4. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.0 (with no JavaScript required) for maximum compatibility across browsers. It has very few requirements and is very easy to configure and install. SquirrelMail has all the functionality you would want from an email client, including strong MIME support, address books, and folder manipulation. Details ------- There is a cross site scripting issue in the decoding of encoded text in certain headers. SquirrelMail correctly decodes the specially crafted header, but doesn't sanitize the decoded strings. Affected -------- SquirrelMail 1.4.3a and earlier SquirrelMail 1.5.1-cvs before 23rd October 2004 Resolution ---------- A patch has been published to resolve this issue for the SquirrelMail 1.4.3a branch, and can be downloaded from here: http://prdownloads.sourceforge.net/squirrelmail/sm143a-xss.diff?download To apply this patch, copy the sm143a-xss.diff file into the base SquirrelMail directory, and follow the command: patch -p0 < sm143a-xss.diff Those using SquirrelMail 1.5.1-cvs should update using CVS, or use a copy of the latest snapshot downloadable from the SquirrelMail website at: http://www.squirrelmail.org Acknowledgements ---------------- Special thanks goes to Joost Pol for notifying us about this issue. Comments -------- The SquirrelMail development team work hard with people reporting security issues in an attempt to resolve issues. We appreciate those that are willing to dedicate the time to work with us on any issue they uncover in the SquirrelMail project. If any further issues are uncovered, a dedicated mail address can be used to report the issue. The address is security@squirrelmail.org. -- Jonathan Angliss (jon@squirrelmail.org)