According to NetSecurity …
The ip_setsockopt() function code is a subroutine of the setsockopt(2) system call. This function allows manipulation of various options of the IP socket. The MCAST_MSFILTER option can be used to provide the kernel with a list of multicast addresses to be received on the socket. This code has been introduced with the 2.4.22/2.6.1 kernel releases. Proper exploitation of this vulnerability leads to local privilege escalation giving an attacker full super-user privileges. Unsuccesfull exploitation of the vulnerability may lead to a denial-of-service attack causing machine crash or instant reboot.
This bug has been fixed in the 2.4.26 and 2.6.4 kernel releases.
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