How severe is CVE-2012-3988?

CVE-2012-3988 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2012-3988 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-3988?

CVE-2012-3988 primarily affects Mozilla Firefox. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-3988?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2012-3988 published?

CVE-2012-3988 was published on 2012-10-10 and last updated on 2026-06-16.

CVE-2012-3988

CVE-2012-3988 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 9.3. 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-416.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Mozilla Firefox
Published: 2012-10-10
Last modified: 2026-06-16

Description

Use-after-free vulnerability in Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbird before 16.0, Thunderbird ESR 10.x before 10.0.8, and SeaMonkey before 2.13 might allow user-assisted remote attackers to execute arbitrary code via vectors involving use of mozRequestFullScreen to enter full-screen mode, and use of the history.back method for backwards history navigation.

Frequently asked questions

What is CVE-2012-3988?: Use-after-free vulnerability in Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbird before 16.0, Thunderbird ESR 10.x before 10.0.8, and SeaMonkey before 2.13 might allow user-assisted remote attackers to execute arbitrary code via vectors involving use of mozRequestFullScreen to enter full-screen mode, and use of the history.back method for backwards history navigation.
How severe is CVE-2012-3988?: CVE-2012-3988 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2012-3988 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-3988?: CVE-2012-3988 primarily affects Mozilla Firefox. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-3988?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2012-3988 published?: CVE-2012-3988 was published on 2012-10-10 and last updated on 2026-06-16.

References

Affected products (21)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird_esr:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:seamonkey:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:10.04:*:*:*:-:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:11.04:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:11.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
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:suse:linux_enterprise_desktop:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_desktop:11:sp3:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_sdk:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:11:sp3:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:11:sp3:*:*:*:vmware:*:*

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Other CWE-416 (Use After Free) vulnerabilities

CVE-2026-13782 — Critical (CVSS 10.0): Use after free in Browser in Google Chrome prior to 150.0.7871.47 allowed a remote attacker who had compromised the…
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CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
CVE-2025-24085 — Critical (CVSS 10.0): A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.3 and iPadOS 18.3,…
CVE-2024-43102 — Critical (CVSS 10.0): Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of…
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