CVE-2012-0477

CVE-2012-0477 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: 2% (79th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-79
• Affected product: Mozilla Firefox
• Published: 2012-04-25
• Last modified: 2026-06-16

Description

Multiple cross-site scripting (XSS) vulnerabilities in Mozilla Firefox 4.x through 11.0, Firefox ESR 10.x before 10.0.4, Thunderbird 5.0 through 11.0, Thunderbird ESR 10.x before 10.0.4, and SeaMonkey before 2.9 allow remote attackers to inject arbitrary web script or HTML via the (1) ISO-2022-KR or (2) ISO-2022-CN character set.

Frequently asked questions

What is CVE-2012-0477?

Multiple cross-site scripting (XSS) vulnerabilities in Mozilla Firefox 4.x through 11.0, Firefox ESR 10.x before 10.0.4, Thunderbird 5.0 through 11.0, Thunderbird ESR 10.x before 10.0.4, and SeaMonkey before 2.9 allow remote attackers to inject arbitrary web script or HTML via the (1) ISO-2022-KR or (2) ISO-2022-CN character set.

How severe is CVE-2012-0477?

CVE-2012-0477 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2012-0477 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-0477?

CVE-2012-0477 primarily affects Mozilla Firefox. In total, 162 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-0477?

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

When was CVE-2012-0477 published?

CVE-2012-0477 was published on 2012-04-25 and last updated on 2026-06-16.

References

• http://secunia.com/advisories/48920
• http://secunia.com/advisories/48922
• http://secunia.com/advisories/48972
• http://secunia.com/advisories/49047
• http://secunia.com/advisories/49055
• http://www.debian.org/security/2012/dsa-2457
• http://www.debian.org/security/2012/dsa-2458
• http://www.debian.org/security/2012/dsa-2464
• http://www.mandriva.com/security/advisories?name=MDVSA-2012:066
• http://www.mandriva.com/security/advisories?name=MDVSA-2012:081
• http://www.mozilla.org/security/announce/2012/mfsa2012-29.html
• http://www.securityfocus.com/bid/53229
• https://bugzilla.mozilla.org/show_bug.cgi?id=718573
• https://exchange.xforce.ibmcloud.com/vulnerabilities/75154
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16889

Affected products (162)

• 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: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:11.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:10.0.3:*:*:*:*:*:*:*
• 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:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:7.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:8.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:9.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:9.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:thunderbird:10.0:*:*:*:*:*:*:*

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