Description
functions/mime.php in SquirrelMail before 1.4.18 does not protect the application's content from Cascading Style Sheets (CSS) positioning in HTML e-mail messages, which allows remote attackers to spoof the user interface, and conduct cross-site scripting (XSS) and phishing attacks, via a crafted message.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 5.0 | squirrelmail | 2:1.4.15-4+lenny1 | DSA-1802-1 |
| Debian 4.0 | squirrelmail | 2:1.4.9a-4 | DSA-1802-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | squirrelmail | 1.4.8-5.el5_3.7 | RHSA-2009:1066 |
| RHEL 4 | squirrelmail | 1.4.8-5.el4_8.5 | RHSA-2009:1066 |
| RHEL 3 | squirrelmail | 1.4.8-13.el3 | RHSA-2009:1066 |
Advisories 2
- DSA-1802-1 squirrelmail - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
- RHSA-2009:1066 Red Hat Security Advisory: squirrelmail security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
References
- APPLE-SA-2010-06-15-1 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=500356
- MDVSA-2009:110 vendor-advisory
- 34916 vdb-entry
- http://squirrelmail.svn.sourceforge.net/viewvc/squirrelmail/branches/SM-1_4-STABLE/squirrelmail/doc/ChangeLog
- ADV-2010-1481 vdb-entry
- oval:org.mitre.oval:def:10441 vdb-entry signature
- FEDORA-2009-4870 vendor-advisory
- 35140 third-party-advisory
- FEDORA-2009-4880 vendor-advisory
- http://www.squirrelmail.org/security/issue/2009-05-12
- http://squirrelmail.svn.sourceforge.net/viewvc/squirrelmail/branches/SM-1_4-STABLE/squirrelmail/functions/mime.php?r1=13667&r2=13666&pathrev=13667
- http://support.apple.com/kb/HT4188
- squirrelmail-css-xss(50463) vdb-entry
- 40220 third-party-advisory
- ADV-2009-1296 vdb-entry
- 35259 third-party-advisory
- 35052 third-party-advisory
- FEDORA-2009-4875 vendor-advisory
- RHSA-2009:1066 vendor-advisory
- 35073 third-party-advisory
- http://squirrelmail.svn.sourceforge.net/viewvc/squirrelmail?view=rev&revision=13667
- DSA-1802 vendor-advisory