CVE-2009-2470

CVE-2009-2470 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-20.

Key facts

• Severity: Medium (CVSS 2.0 base score 5.0)
• EPSS exploit prediction: 2% (78th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-20
• Affected product: Mozilla Firefox
• Published: 2009-08-04
• Last modified: 2026-06-16

Description

Mozilla Firefox before 3.0.12, and 3.5.x before 3.5.2, allows remote SOCKS5 proxy servers to cause a denial of service (data stream corruption) via a long domain name in a reply.

Frequently asked questions

What is CVE-2009-2470?

Mozilla Firefox before 3.0.12, and 3.5.x before 3.5.2, allows remote SOCKS5 proxy servers to cause a denial of service (data stream corruption) via a long domain name in a reply.

How severe is CVE-2009-2470?

CVE-2009-2470 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2009-2470 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-2470?

CVE-2009-2470 primarily affects Mozilla Firefox. In total, 103 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-2470?

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

When was CVE-2009-2470 published?

CVE-2009-2470 was published on 2009-08-04 and last updated on 2026-06-16.

References

• http://secunia.com/advisories/36126
• http://sunsolve.sun.com/search/document.do?assetkey=1-66-266148-1
• http://www.mozilla.org/security/announce/2009/mfsa2009-38.html
• http://www.redhat.com/support/errata/RHSA-2010-0153.html
• http://www.redhat.com/support/errata/RHSA-2010-0154.html
• http://www.securityfocus.com/bid/35925
• http://www.securitytracker.com/id?1022665
• http://www.vupen.com/english/advisories/2009/2142
• http://www.vupen.com/english/advisories/2010/0650
• https://bugzilla.mozilla.org/show_bug.cgi?id=459524
• https://exchange.xforce.ibmcloud.com/vulnerabilities/52252
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10197
• https://www.redhat.com/archives/fedora-package-announce/2009-August/msg00198.html
• https://www.redhat.com/archives/fedora-package-announce/2009-August/msg00261.html

Affected products (103)

• cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.3:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.4:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.5:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.6:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.6.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.7:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.7.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.8:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.9:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.9:rc:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.9.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.9.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.9.3:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.9_rc:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.10:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:0.10.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0:preview_release:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.4:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.5:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.6:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.6:*:linux:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.7:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.0.8:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.4.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5:beta1:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5:beta2:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5.0.4:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5.0.5:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5.0.6:*:*:*:*:*:*:*

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