CVE-2009-3986

CVE-2009-3986 is a high-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 7.6. 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-94.

Key facts

Description

Mozilla Firefox before 3.0.16 and 3.5.x before 3.5.6, and SeaMonkey before 2.0.1, allows remote attackers to execute arbitrary JavaScript with chrome privileges by leveraging a reference to a chrome window from a content window, related to the window.opener property.

Frequently asked questions

What is CVE-2009-3986?
Mozilla Firefox before 3.0.16 and 3.5.x before 3.5.6, and SeaMonkey before 2.0.1, allows remote attackers to execute arbitrary JavaScript with chrome privileges by leveraging a reference to a chrome window from a content window, related to the window.opener property.
How severe is CVE-2009-3986?
CVE-2009-3986 has a CVSS 2.0 base score of 7.6, rated high severity.
Is CVE-2009-3986 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-3986?
CVE-2009-3986 primarily affects Mozilla Firefox. In total, 156 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-3986?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2009-3986 published?
CVE-2009-3986 was published on 2009-12-17 and last updated on 2026-06-16.

References

Affected products (156)

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