CVE-2012-4191

The mozilla::net::FailDelayManager::Lookup function in the WebSockets implementation in Mozilla...

9.3 HighFix available

CVE-2012-4191 is a high vulnerability (CVSS 9.3) in Mozilla Firefox, published October 12, 2012. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 3.87%, the 90th percentile. Fixed in MozillaFirefox 50.1.0-1.1.

The mozilla::net::FailDelayManager::Lookup function in the WebSockets implementation in Mozilla Firefox before 16.0.1, Thunderbird before 16.0.1, and SeaMonkey before 2.13.1 allows remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unspecified vectors.

Exploit likelihood

3.87%Down 2.7 points since Feb 4, 2022

What each source reports

NVD Score used 9.3

Record: CVE-2012-4191
CVSS 2.0: 9.3 HighAV:N/AC:M/Au:N/C:C/I:C/A:C
Weakness: CWE-787
Updated: 2026-11-02

CVE List No score

Record: CVE-2012-4191
Updated: 2026-11-02

EUVDEUVD-2012-4135 No score

Record: EUVD-2012-4135
Updated: 2026-11-03

GitHub AdvisoriesGHSA-xrwr-pg2p-3r5m No score

The mozilla::net::FailDelayManager::Lookup function in the WebSockets implementation in Mozilla...

Record: GHSA-xrwr-pg2p-3r5m
Weakness: CWE-787
Updated: 2026-11-02

OSVopenSUSE-SU-2024:10071-1 No score

MozillaFirefox-50.1.0-1.1 on GA media

These are all security issues fixed in the MozillaFirefox-50.1.0-1.1 package on the GA media of openSUSE Tumbleweed.

Record: openSUSE-SU-2024:10071-1
Updated: 2026-11-02

OSVopenSUSE-SU-2024:10218-1 No score

seamonkey-2.40-6.1 on GA media

These are all security issues fixed in the seamonkey-2.40-6.1 package on the GA media of openSUSE Tumbleweed.

Record: openSUSE-SU-2024:10218-1
Updated: 2026-11-02

OSVopenSUSE-SU-2024:10230-1 No score

MozillaThunderbird-45.5.1-1.1 on GA media

These are all security issues fixed in the MozillaThunderbird-45.5.1-1.1 package on the GA media of openSUSE Tumbleweed.

Record: openSUSE-SU-2024:10230-1
Updated: 2026-11-02

OSVopenSUSE-SU-2024:14572-1 No score

firefox-esr-128.5.1-1.1 on GA media

These are all security issues fixed in the firefox-esr-128.5.1-1.1 package on the GA media of openSUSE Tumbleweed.

Record: openSUSE-SU-2024:14572-1
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`MozillaFirefox` openSUSE:Tumbleweed	before 50.1.0-1.1	50.1.0-1.1
`MozillaThunderbird` openSUSE:Tumbleweed	before 45.5.1-1.1	45.5.1-1.1
`firefox-esr` openSUSE:Tumbleweed	before 128.5.1-1.1	128.5.1-1.1