CVE-2011-2999

CVE-2011-2999 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 4.3. 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-264.

Key facts

Description

Mozilla Firefox before 3.6.23 and 4.x through 5, Thunderbird before 6.0, and SeaMonkey before 2.3 do not properly handle "location" as the name of a frame, which allows remote attackers to bypass the Same Origin Policy via a crafted web site, a different vulnerability than CVE-2010-0170.

Frequently asked questions

What is CVE-2011-2999?
Mozilla Firefox before 3.6.23 and 4.x through 5, Thunderbird before 6.0, and SeaMonkey before 2.3 do not properly handle "location" as the name of a frame, which allows remote attackers to bypass the Same Origin Policy via a crafted web site, a different vulnerability than CVE-2010-0170.
How severe is CVE-2011-2999?
CVE-2011-2999 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2011-2999 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-2999?
CVE-2011-2999 primarily affects Mozilla Firefox. In total, 204 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-2999?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-2999 published?
CVE-2011-2999 was published on 2011-09-29 and last updated on 2026-06-16.

References

Affected products (204)

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