|Check Point Reference:||CPAI-2005-298|
|Date Published:||3 Nov 2009|
|Last Updated:||3 Oct 2018|
|Protection Provided by:||
|Who is Vulnerable?|
|Vulnerability Description||The Squid proxy server is an open source, Internet proxy and caching application. It supports the proxying of FTP, HTTP, SSL, and DNS services. The default proxy service port is 3128/TCP. A vulnerability exists in the Squid proxy server in the processing of authentication requests. The flaw is caused by improper handling of malformed NTLM authentication requests. By sending such crafted HTTP requests to the target, a remote malicious user may exploit this vulnerability to terminate an affected Squid proxy server, creating a denial of service condition. Upon receiving a crafted NTLM authentication message, the Squid proxy server will terminate and reset all established connections. However, the Squid monitor process will respawn the worker process automatically which restores the proxy services. If the attack is launched continuously, the target Squid proxy may be put into a lasting denial-of-service condition.|
This protection will detect and block attempts to exploit this vulnerability
In order for the protection to be activated, update your Security Gateway product to the latest IPS update. For information on how to update IPS, go to SBP-2006-05, click on Protection tab and select the version of your choice.
This protection's log will contain the following information:
Attack Name: Proxy Server Enforcement Violation.
Attack Information: Squid Authentication Headers Handling Denial of Service