How severe is CVE-2009-3371?

CVE-2009-3371 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2009-3371 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-3371?

CVE-2009-3371 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-3371?

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-2009-3371 published?

CVE-2009-3371 was published on 2009-10-29 and last updated on 2026-06-16.

CVE-2009-3371

CVE-2009-3371 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 10.0. 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-399.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 7% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-399
Affected product: Mozilla Firefox
Published: 2009-10-29
Last modified: 2026-06-16

Description

Use-after-free vulnerability in Mozilla Firefox 3.5.x before 3.5.4 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code by creating JavaScript web-workers recursively.

Frequently asked questions

What is CVE-2009-3371?: Use-after-free vulnerability in Mozilla Firefox 3.5.x before 3.5.4 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code by creating JavaScript web-workers recursively.
How severe is CVE-2009-3371?: CVE-2009-3371 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2009-3371 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-3371?: CVE-2009-3371 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-3371?: 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-2009-3371 published?: CVE-2009-3371 was published on 2009-10-29 and last updated on 2026-06-16.

References

Affected products (4)

cpe:2.3:a:mozilla:firefox:3.5.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.5.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.5.3:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.5.4:*:*:*:*:*:*:*

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Other CWE-399 (Resource Management Errors) vulnerabilities

CVE-2015-8104 — Critical (CVSS 10.0): The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a…
CVE-2015-0339 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0335 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0333 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2014-4121 — Critical (CVSS 10.0): Microsoft .NET Framework 2.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2 does not properly parse internationalized…
CVE-2014-0560 — Critical (CVSS 10.0): Use-after-free vulnerability in Adobe Reader and Acrobat 10.x before 10.1.12 and 11.x before 11.0.09 on Windows and OS…

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