How severe is CVE-2011-3659?

CVE-2011-3659 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2011-3659 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 37% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-3659?

CVE-2011-3659 primarily affects Mozilla Firefox. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-3659?

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-2011-3659 published?

CVE-2011-3659 was published on 2012-02-01 and last updated on 2026-06-16.

CVE-2011-3659

CVE-2011-3659 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 37% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-416.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 37% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Mozilla Firefox
Published: 2012-02-01
Last modified: 2026-06-16

Description

Use-after-free vulnerability in Mozilla Firefox before 3.6.26 and 4.x through 9.0, Thunderbird before 3.1.18 and 5.0 through 9.0, and SeaMonkey before 2.7 might allow remote attackers to execute arbitrary code via vectors related to incorrect AttributeChildRemoved notifications that affect access to removed nsDOMAttribute child nodes.

Frequently asked questions

What is CVE-2011-3659?: Use-after-free vulnerability in Mozilla Firefox before 3.6.26 and 4.x through 9.0, Thunderbird before 3.1.18 and 5.0 through 9.0, and SeaMonkey before 2.7 might allow remote attackers to execute arbitrary code via vectors related to incorrect AttributeChildRemoved notifications that affect access to removed nsDOMAttribute child nodes.
How severe is CVE-2011-3659?: CVE-2011-3659 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2011-3659 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 37% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-3659?: CVE-2011-3659 primarily affects Mozilla Firefox. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-3659?: 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-2011-3659 published?: CVE-2011-3659 was published on 2012-02-01 and last updated on 2026-06-16.

References

Affected products (11)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:seamonkey:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:11.4:*:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_desktop:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_desktop:11:sp1:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:11:sp1:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:11:sp1:*:*:*:vmware:*:*
cpe:2.3:o:suse:linux_enterprise_software_development_kit:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_software_development_kit:11:sp1:*:*:*:*:*:*

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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…
CVE-2026-4725 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149…
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…
CVE-2021-32495 — Critical (CVSS 10.0): Radare2 has a use-after-free vulnerability in pyc parser's get_none_object function. Attacker can read freed memory…

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