CVE-2009-3983: Mozilla Firefox

Medium severity, CVSS 6.8. EPSS: 2.2% chance of exploitation in the next 30 days.

Mozilla Firefox before 3.0.16 and 3.5.x before 3.5.6, and SeaMonkey before 2.0.1, allows remote attackers to send authenticated requests to arbitrary applications by replaying the NTLM credentials of a browser user.

Affected products

• Mozilla Firefox: up to and including 3.0.15; version 0.1 only; version 0.2 only; version 0.3 only; version 0.4 only; version 0.5 only; …
• Mozilla Seamonkey: up to and including 2.0; version 1.0 only; version 1.0.1 only; version 1.0.2 only; version 1.0.3 only; version 1.0.4 only; …
• Mozilla Thunderbird: any version

Published 2009-12-17. Last modified 2026-06-16.