Linksys WRT54g firmware 1.00.9 does not require credentials when making configuration changes, which allows remote attackers to modify arbitrary configurations via a direct request to Security.tri, as demonstrated using the SecurityMode and layout parameters, a different issue than CVE-2006-2559.

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.

Linksys WRT54G routers version 5 (running VXWorks) allow remote attackers to cause a denial of service by sending a malformed DCC SEND string to an IRC channel, which causes an IRC connection reset, possibly related to the masquerading code for NAT environments, and as demonstrated via (1) a DCC SEND with a single long argument, or (2) a DCC SEND with IP, port, and filesize arguments with a 0 value.

Linksys WRT54GS and BEFW11S4 allows remote attackers to cause a denial of service (device crash) via an IP packet with the same source and destination IPs and ports, and with the SYN flag set (aka LAND). NOTE: the provenance of this issue is unknown; the details are obtained solely from the BID.

Buffer overflow in apply.cgi in Linksys WRT54G 3.01.03, 3.03.6, and possibly other versions before 4.20.7, allows remote attackers to execute arbitrary code via a long HTTP POST request.

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.

Linksys WRT54G router allows remote attackers to cause a denial of service (CPU consumption and server hang) via an HTTP POST request with a negative Content-Length value.

Linksys WRT54G 3.01.03, 3.03.6, 4.00.7, and possibly other versions before 4.20.7, does not verify user authentication until after an HTTP POST request has been processed, which allows remote attackers to (1) modify configuration using restore.cgi or (2) upload new firmware using upgrade.cgi.

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.

Unknown vulnerability in Linksys WRT54GS wireless router with firmware 4.50.6, with WPA Personal/TKIP authentication enabled, allows remote clients to bypass authentication by connecting without using encryption.