Squid 2.7.x < 3.0 DoS
High Nessus Network Monitor Plugin ID 8636
SynopsisThe remote proxy server is affected by a denial of service vulnerability.
DescriptionSquid versions 2.7.x prior to 3.0 are affected by a denial of service vulnerability due to a miscalculation of memory size when handling HTTP header values. Specifically, this issue affects the 'httpMakeVaryMark()' function of the 'src/http.cc' source file. This causes an assertion to fail, and repeated failures can cause the service to terminate.
A remote attacker can exploit this vulnerability by sending a specially crafted HTTP request. Authentication may or may not be required depending on the server's configuration. Successful exploitation will cause the Squid service to terminate.
SolutionEither upgrade to Squid version 3.0 or later, or apply the vendor-supplied patch.