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.

ezconfig.asp in Linksys WRT54G router 3.01.03, 3.03.6, non-default configurations of 2.04.4, and possibly other versions, does not use an authentication initialization function, which allows remote attackers to obtain encrypted configuration information and, if the key is known, modify the configuration.