CVE-2006-2559: Linksys WRT54G

High severity, CVSS 7.5. EPSS: 1.7% chance of exploitation in the next 30 days.

Linksys WRT54G Wireless-G Broadband Router allows remote attackers to bypass access restrictions and conduct unauthorized operations via a UPnP request with a modified InternalClient parameter, which is not validated, as demonstrated by using AddPortMapping to forward arbitrary traffic.

Affected products

• Linksys WRT54G: version 1.42.3 only; version 2.00.8 only; version 2.02.7 only; version 2.04.4 only; version 2.04.4_non_default only; version 3.01.3 only; …
• Linksys WRT54G v5: any version

Published 2006-05-24. Last modified 2026-06-16.