CVE-2012-1961

CVE-2012-1961 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-20.

Key facts

• Severity: Medium (CVSS 2.0 base score 4.3)
• EPSS exploit prediction: 2% (80th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-20
• Affected product: Mozilla Firefox
• Published: 2012-07-18
• Last modified: 2026-06-16

Description

Mozilla Firefox 4.x through 13.0, Firefox ESR 10.x before 10.0.6, Thunderbird 5.0 through 13.0, Thunderbird ESR 10.x before 10.0.6, and SeaMonkey before 2.11 do not properly handle duplicate values in X-Frame-Options headers, which makes it easier for remote attackers to conduct clickjacking attacks via a FRAME element referencing a web site that produces these duplicate values.

Frequently asked questions

What is CVE-2012-1961?

Mozilla Firefox 4.x through 13.0, Firefox ESR 10.x before 10.0.6, Thunderbird 5.0 through 13.0, Thunderbird ESR 10.x before 10.0.6, and SeaMonkey before 2.11 do not properly handle duplicate values in X-Frame-Options headers, which makes it easier for remote attackers to conduct clickjacking attacks via a FRAME element referencing a web site that produces these duplicate values.

How severe is CVE-2012-1961?

CVE-2012-1961 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2012-1961 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-1961?

CVE-2012-1961 primarily affects Mozilla Firefox. In total, 127 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-1961?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2012-1961 published?

CVE-2012-1961 was published on 2012-07-18 and last updated on 2026-06-16.

References

• http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00011.html
• http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00012.html
• http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00013.html
• http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00016.html
• http://osvdb.org/84003
• http://rhn.redhat.com/errata/RHSA-2012-1088.html
• http://secunia.com/advisories/49965
• http://secunia.com/advisories/49968
• http://secunia.com/advisories/49972
• http://secunia.com/advisories/49977
• http://secunia.com/advisories/49979
• http://secunia.com/advisories/49992
• http://secunia.com/advisories/49993
• http://secunia.com/advisories/49994
• http://www.mozilla.org/security/announce/2012/mfsa2012-51.html
• http://www.securityfocus.com/bid/54584
• http://www.securitytracker.com/id?1027256
• http://www.securitytracker.com/id?1027257
• http://www.securitytracker.com/id?1027258
• http://www.ubuntu.com/usn/USN-1509-1
• http://www.ubuntu.com/usn/USN-1509-2
• http://www.ubuntu.com/usn/USN-1510-1
• https://bugzilla.mozilla.org/show_bug.cgi?id=761655
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16993

Affected products (127)

• cpe:2.3:a:mozilla:firefox:4.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta1:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta10:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta11:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta12:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta2:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta3:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta4:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta5:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta6:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta7:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta8:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0:beta9:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:4.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:5.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:5.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:6.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:6.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:6.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:7.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:7.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:8.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:8.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:9.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:9.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:11.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:12.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:12.0:beta6:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:13.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.4:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.5:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:5.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:6.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:6.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:6.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:7.0:*:*:*:*:*:*:*

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