CVE-2012-1962

CVE-2012-1962 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-399.

Key facts

• Severity: Critical (CVSS 2.0 base score 10.0)
• EPSS exploit prediction: 5% (92nd percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-399
• Affected product: Mozilla Firefox
• Published: 2012-07-18
• Last modified: 2026-06-16

Description

Use-after-free vulnerability in the JSDependentString::undepend function in Mozilla Firefox 4.x through 13.0, Firefox ESR 10.x before 10.0.6, Thunderbird 5.0 through 13.0, Thunderbird ESR 10.x before 10.0.6, and SeaMonkey before 2.11 allows remote attackers to cause a denial of service (memory corruption) or possibly execute arbitrary code via vectors involving strings with multiple dependencies.

Frequently asked questions

What is CVE-2012-1962?

Use-after-free vulnerability in the JSDependentString::undepend function in Mozilla Firefox 4.x through 13.0, Firefox ESR 10.x before 10.0.6, Thunderbird 5.0 through 13.0, Thunderbird ESR 10.x before 10.0.6, and SeaMonkey before 2.11 allows remote attackers to cause a denial of service (memory corruption) or possibly execute arbitrary code via vectors involving strings with multiple dependencies.

How severe is CVE-2012-1962?

CVE-2012-1962 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2012-1962 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-1962?

CVE-2012-1962 primarily affects Mozilla Firefox. In total, 127 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-1962?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2012-1962 published?

CVE-2012-1962 was published on 2012-07-18 and last updated on 2026-06-16.

References

• http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00011.html
• http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00012.html
• http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00013.html
• http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00016.html
• http://osvdb.org/84004
• http://rhn.redhat.com/errata/RHSA-2012-1088.html
• http://secunia.com/advisories/49965
• http://secunia.com/advisories/49968
• http://secunia.com/advisories/49972
• http://secunia.com/advisories/49977
• http://secunia.com/advisories/49979
• http://secunia.com/advisories/49992
• http://secunia.com/advisories/49993
• http://secunia.com/advisories/49994
• http://www.mozilla.org/security/announce/2012/mfsa2012-52.html
• http://www.securityfocus.com/bid/54575
• http://www.securitytracker.com/id?1027256
• http://www.securitytracker.com/id?1027257
• http://www.securitytracker.com/id?1027258
• http://www.ubuntu.com/usn/USN-1509-1
• http://www.ubuntu.com/usn/USN-1509-2
• http://www.ubuntu.com/usn/USN-1510-1
• https://bugzilla.mozilla.org/show_bug.cgi?id=764296
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16729

Affected products (127)

• cpe:2.3:a:mozilla:firefox:4.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta1:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta10:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta11:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta12:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta2:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta3:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta4:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta5:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta6:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta7:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta8:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta9:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:5.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:5.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:6.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:6.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:6.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:7.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:7.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:8.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:8.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:9.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:9.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:11.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:12.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:12.0:beta6:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:13.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.4:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.5:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:5.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:6.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:6.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:6.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:7.0:*:*:*:*:*:*:*

More vulnerabilities in Mozilla Firefox

• CVE-2026-4725 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149…
• CVE-2026-4692 — Critical (CVSS 10.0): Sandbox escape in the Responsive Design Mode component. This vulnerability was fixed in Firefox 149, Firefox ESR…
• CVE-2026-4689 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability was…
• CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
• CVE-2026-2778 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in…
• CVE-2026-2776 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability…

All CVEs affecting Mozilla Firefox →

Other CWE-399 (Resource Management Errors) vulnerabilities

• CVE-2015-8104 — Critical (CVSS 10.0): The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a…
• CVE-2015-0339 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
• CVE-2015-0335 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
• CVE-2015-0333 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
• CVE-2014-4121 — Critical (CVSS 10.0): Microsoft .NET Framework 2.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2 does not properly parse internationalized…
• CVE-2014-0560 — Critical (CVSS 10.0): Use-after-free vulnerability in Adobe Reader and Acrobat 10.x before 10.1.12 and 11.x before 11.0.09 on Windows and OS…

Browse all CWE-399 (Resource Management Errors) vulnerabilities →