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.

ezconfig.asp in Linksys WRT54G router 3.01.03, 3.03.6, non-default configurations of 2.04.4, and possibly other versions, uses weak encryption (XOR encoding with a fixed byte mask) for configuration information, which could allow attackers to decrypt the information and possibly re-encrypt it in conjunction with CVE-2005-2914.