CVE-2009-3376

Severity: critical (CVSS 9.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2009-10-29 · updated 2026-06-16
Weakness: CWE-16

Description

Mozilla Firefox before 3.0.15 and 3.5.x before 3.5.4, and SeaMonkey before 2.0, does not properly handle a right-to-left override (aka RLO or U+202E) Unicode character in a download filename, which allows remote attackers to spoof file extensions via a crafted filename, as demonstrated by displaying a non-executable extension for an executable file.

Affected products

Mozilla Firefox: 3.0-beta5, 3.0.1, 3.0.2, 3.0.3, 3.0.4, 3.0.5 (+11)
Mozilla Seamonkey: through 1.5.0.10; 1.0, 1.0-alpha, 1.0-beta, 1.0.1, 1.0.2, 1.0.3 (+28)

References

http://lists.opensuse.org/opensuse-security-announce/2010-06/msg00001.html
http://secunia.com/advisories/38977
http://sunsolve.sun.com/search/document.do?assetkey=1-26-272909-1
http://www.mandriva.com/security/advisories?name=MDVSA-2009:294
http://www.mozilla.org/security/announce/2009/mfsa2009-62.html
http://www.redhat.com/support/errata/RHSA-2010-0153.html
http://www.redhat.com/support/errata/RHSA-2010-0154.html
http://www.ubuntu.com/usn/USN-915-1
http://www.vupen.com/english/advisories/2009/3334
http://www.vupen.com/english/advisories/2010/0648
http://www.vupen.com/english/advisories/2010/0650
https://bugzilla.mozilla.org/show_bug.cgi?id=511521

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