How severe is CVE-2009-2953?

CVE-2009-2953 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2009-2953 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-2009-2953?

CVE-2009-2953 primarily affects Mozilla Firefox. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-2953?

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

When was CVE-2009-2953 published?

CVE-2009-2953 was published on 2009-08-24 and last updated on 2026-06-16.

CVE-2009-2953

CVE-2009-2953 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 5.0. 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: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-399
Affected product: Mozilla Firefox
Published: 2009-08-24
Last modified: 2026-06-16

Description

Mozilla Firefox 3.0.6 through 3.0.13, and 3.5.x, allows remote attackers to cause a denial of service (CPU consumption) via JavaScript code with a long string value for the hash property (aka location.hash), a related issue to CVE-2008-5715.

Frequently asked questions

What is CVE-2009-2953?: Mozilla Firefox 3.0.6 through 3.0.13, and 3.5.x, allows remote attackers to cause a denial of service (CPU consumption) via JavaScript code with a long string value for the hash property (aka location.hash), a related issue to CVE-2008-5715.
How severe is CVE-2009-2953?: CVE-2009-2953 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2009-2953 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-2009-2953?: CVE-2009-2953 primarily affects Mozilla Firefox. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-2953?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-2953 published?: CVE-2009-2953 was published on 2009-08-24 and last updated on 2026-06-16.

References

Affected products (13)

cpe:2.3:a:mozilla:firefox:3.0.6:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.7:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.8:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.9:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.10:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.11:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.12:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.13:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.5:*:*:*:*:*:*:*
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

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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…
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