What’s Vulnerable › Vulnerabilities

CVE-2012-3989

• Severity: critical (CVSS 9.3 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.5% 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, Thunderbird before 16.0, and SeaMonkey before 2.13 do not properly perform a cast of an unspecified variable during use of the instanceof operator on a JavaScript object, which allows remote attackers to execute arbitrary code or cause a denial of service (assertion failure) via a crafted web site.

Affected products

• Canonical Ubuntu Linux: 10.04, 11.04, 11.10, 12.04
• Mozilla Firefox: before 16.0 — fixed in 16.0
• Mozilla Seamonkey: before 2.13 — fixed in 2.13
• Mozilla Thunderbird: before 16.0 — fixed in 16.0
• SUSE Linux Enterprise Server 15 SP1: 10-sp4, 11-sp2
• SUSE Linux Enterprise Server: 10-sp4, 11-sp2

How to fix

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

References

• http://lists.opensuse.org/opensuse-security-announce/2012-10/msg00010.html
• http://osvdb.org/86097
• http://secunia.com/advisories/50856
• http://secunia.com/advisories/50892
• http://secunia.com/advisories/50904
• http://secunia.com/advisories/50935
• http://secunia.com/advisories/50984
• http://www.mozilla.org/security/announce/2012/mfsa2012-80.html
• http://www.ubuntu.com/usn/USN-1611-1
• https://bugzilla.mozilla.org/show_bug.cgi?id=783867
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16814
• http://lists.opensuse.org/opensuse-security-announce/2012-10/msg00010.html

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