CVE-2012-3978

CVE-2012-3978 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 6.8. 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

The nsLocation::CheckURL function in Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, Thunderbird before 15.0, Thunderbird ESR 10.x before 10.0.7, and SeaMonkey before 2.12 does not properly follow the security model of the location object, which allows remote attackers to bypass intended content-loading restrictions or possibly have unspecified other impact via vectors involving chrome code.

Frequently asked questions

What is CVE-2012-3978?
The nsLocation::CheckURL function in Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, Thunderbird before 15.0, Thunderbird ESR 10.x before 10.0.7, and SeaMonkey before 2.12 does not properly follow the security model of the location object, which allows remote attackers to bypass intended content-loading restrictions or possibly have unspecified other impact via vectors involving chrome code.
How severe is CVE-2012-3978?
CVE-2012-3978 has a CVSS 2.0 base score of 6.8, rated medium severity.
Is CVE-2012-3978 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-3978?
CVE-2012-3978 primarily affects Mozilla Firefox. In total, 339 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-3978?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2012-3978 published?
CVE-2012-3978 was published on 2012-08-29 and last updated on 2026-06-16.

References

Affected products (339)

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