CVE-2009-3978

Severity: medium (CVSS 4.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2009-11-19 · updated 2026-06-16

Description

The nsGIFDecoder2::GifWrite function in decoders/gif/nsGIFDecoder2.cpp in libpr0n in Mozilla Firefox before 3.5.5 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via an animated GIF file with a large image size, a different vulnerability than CVE-2009-3373.

Affected products

Mozilla Firefox: through 3.5.4; 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 (+63)

References

http://hg.mozilla.org/releases/mozilla-1.9.1/rev/edf189567edc
http://www.h-online.com/open/news/item/Mozilla-fixes-critical-bugs-with-Firefox-3-5-5-852070.html
http://www.mozilla.com/en-US/firefox/3.5.5/releasenotes/
https://bugzilla.mozilla.org/show_bug.cgi?id=525326
https://wiki.mozilla.org/Releases/Firefox_3.5.5/Test_Plan
http://hg.mozilla.org/releases/mozilla-1.9.1/rev/edf189567edc
http://www.h-online.com/open/news/item/Mozilla-fixes-critical-bugs-with-Firefox-3-5-5-852070.html
http://www.mozilla.com/en-US/firefox/3.5.5/releasenotes/
https://bugzilla.mozilla.org/show_bug.cgi?id=525326
https://wiki.mozilla.org/Releases/Firefox_3.5.5/Test_Plan

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