CVE-2012-3962

CVE-2012-3962 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 9.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, Thunderbird before 15.0, Thunderbird ESR 10.x before 10.0.7, and SeaMonkey before 2.12 do not properly iterate through the characters in a text run, which allows remote attackers to execute arbitrary code via a crafted document.

Frequently asked questions

What is CVE-2012-3962?
Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, Thunderbird before 15.0, Thunderbird ESR 10.x before 10.0.7, and SeaMonkey before 2.12 do not properly iterate through the characters in a text run, which allows remote attackers to execute arbitrary code via a crafted document.
How severe is CVE-2012-3962?
CVE-2012-3962 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2012-3962 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-3962?
CVE-2012-3962 primarily affects Mozilla Firefox. In total, 339 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-3962?
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-2012-3962 published?
CVE-2012-3962 was published on 2012-08-29 and last updated on 2026-06-16.

References

Affected products (339)

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