CVE-2012-4187

Severity: critical (CVSS 9.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 6.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2012-10-10 · updated 2026-06-16
Weakness: CWE-119

Description

Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbird before 16.0, Thunderbird ESR 10.x before 10.0.8, and SeaMonkey before 2.13 do not properly manage a certain insPos variable, which allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption and assertion failure) via unspecified vectors.

Affected products

Canonical Ubuntu Linux: 10.04, 11.04, 11.10, 12.04
Mozilla Firefox: before 10.0.8; before 16.0 — fixed in 10.0.8, 16.0
Mozilla Seamonkey: before 2.13 — fixed in 2.13
Mozilla Thunderbird: before 16.0 — fixed in 16.0
Mozilla Thunderbird ESR: before 10.0.8 — fixed in 10.0.8
RedHat Enterprise Linux Desktop: 5.0, 6.0
RedHat Enterprise Linux Eus: 6.3
RedHat Enterprise Linux Server: 5.0, 6.0
RedHat Enterprise Linux Workstation: 5.0, 6.0
SUSE Linux Enterprise Server 15 SP1: 10-sp4, 11-sp3
SUSE Linux Enterprise Sdk: 10-sp4
SUSE Linux Enterprise Server: 10-sp4, 11-sp3

How to fix

Upgrade to a fixed version: Mozilla Firefox 10.0.8, 16.0; Mozilla Seamonkey 2.13; Mozilla Thunderbird 16.0; Mozilla Thunderbird ESR 10.0.8. Check the vendor advisory for mitigations.

References

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