How severe is CVE-2012-4209?

CVE-2012-4209 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2012-4209 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-4209?

CVE-2012-4209 primarily affects Mozilla Firefox. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-4209?

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

When was CVE-2012-4209 published?

CVE-2012-4209 was published on 2012-11-21 and last updated on 2026-06-16.

CVE-2012-4209

CVE-2012-4209 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-79.

Key facts

Severity: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Mozilla Firefox
Published: 2012-11-21
Last modified: 2026-06-16

Description

Mozilla Firefox before 17.0, Firefox ESR 10.x before 10.0.11, Thunderbird before 17.0, Thunderbird ESR 10.x before 10.0.11, and SeaMonkey before 2.14 do not prevent use of a "top" frame name-attribute value to access the location property, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via vectors involving a binary plugin.

Frequently asked questions

What is CVE-2012-4209?: Mozilla Firefox before 17.0, Firefox ESR 10.x before 10.0.11, Thunderbird before 17.0, Thunderbird ESR 10.x before 10.0.11, and SeaMonkey before 2.14 do not prevent use of a "top" frame name-attribute value to access the location property, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via vectors involving a binary plugin.
How severe is CVE-2012-4209?: CVE-2012-4209 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2012-4209 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-4209?: CVE-2012-4209 primarily affects Mozilla Firefox. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-4209?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2012-4209 published?: CVE-2012-4209 was published on 2012-11-21 and last updated on 2026-06-16.

References

Affected products (25)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:seamonkey:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird_esr:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:11.4:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:12.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:12.2:*:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_desktop:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_desktop:11:sp2:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:11:sp2:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:11:sp2:*:*:*:vmware:*:*
cpe:2.3:o:suse:linux_enterprise_software_development_kit:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_software_development_kit:11:sp2:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:5.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:6.3:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:5.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:5.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:10.04:*:*:*:-:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:11.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.10:*:*:*:*:*:*:*

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