CVE-2009-2654

CVE-2009-2654 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 5.8. 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 5.8)
• EPSS exploit prediction: 5% (91st percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-20
• Affected product: Mozilla Firefox
• Published: 2009-08-03
• Last modified: 2026-06-16

Description

Mozilla Firefox before 3.0.13, and 3.5.x before 3.5.2, allows remote attackers to spoof the address bar, and possibly conduct phishing attacks, via a crafted web page that calls window.open with an invalid character in the URL, makes document.write calls to the resulting object, and then calls the stop method during the loading of the error page.

Frequently asked questions

What is CVE-2009-2654?

Mozilla Firefox before 3.0.13, and 3.5.x before 3.5.2, allows remote attackers to spoof the address bar, and possibly conduct phishing attacks, via a crafted web page that calls window.open with an invalid character in the URL, makes document.write calls to the resulting object, and then calls the stop method during the loading of the error page.

How severe is CVE-2009-2654?

CVE-2009-2654 has a CVSS 2.0 base score of 5.8, rated medium severity.

Is CVE-2009-2654 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-2009-2654?

CVE-2009-2654 primarily affects Mozilla Firefox. In total, 108 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-2654?

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

When was CVE-2009-2654 published?

CVE-2009-2654 was published on 2009-08-03 and last updated on 2026-06-16.

References

• http://blog.mozilla.com/security/2009/07/28/url-bar-spoofing-vulnerability/
• http://es.geocities.com/jplopezy/firefoxspoofing.html
• http://osvdb.org/56717
• http://secunia.com/advisories/36001
• http://secunia.com/advisories/36126
• http://secunia.com/advisories/36141
• http://secunia.com/advisories/36435
• http://secunia.com/advisories/36669
• http://secunia.com/advisories/36670
• http://sunsolve.sun.com/search/document.do?assetkey=1-66-266148-1
• http://www.debian.org/security/2009/dsa-1873
• http://www.mozilla.org/security/announce/2009/mfsa2009-44.html
• http://www.redhat.com/support/errata/RHSA-2009-1430.html
• http://www.redhat.com/support/errata/RHSA-2009-1431.html
• http://www.redhat.com/support/errata/RHSA-2009-1432.html
• http://www.securityfocus.com/archive/1/505242/30/0/threaded
• http://www.securityfocus.com/archive/1/505265
• http://www.securityfocus.com/bid/35803
• http://www.securitytracker.com/id?1022603
• http://www.vupen.com/english/advisories/2009/2006
• http://www.vupen.com/english/advisories/2009/2142
• https://bugzilla.mozilla.org/show_bug.cgi?id=451898
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A9686
• https://usn.ubuntu.com/811-1/
• 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 (108)

• 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:1.0.7:*:*:*:*:*:*:*
• 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:*:*:*:*:*:*:*
• cpe:2.3:a:mozilla:firefox:1.5.0.7:*:*:*:*:*:*:*

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