Red Hat Security Advisory: kernel security update

Important

The Internet Group Management Protocol (IGMP) allows local users to cause a denial of service via an IGMP membership report to a target's Ethernet address instead of the Multicast group address, which causes the target to stop sending reports to the router and effectively disconnect the group from the network.

Multiple drivers in Linux kernel 2.4.19 and earlier do not properly mark memory with the VM_IO flag, which causes incorrect reference counts and may lead to a denial of service (kernel panic) when accessing freed kernel pages.

The search_binary_handler function in exec.c in Linux 2.4 kernel on 64-bit x86 architectures does not check a return code for a particular function call when virtual memory is low, which allows local users to cause a denial of service (panic), as demonstrated by running a process using the bash ulimit -v command.

The sysctl functionality (sysctl.c) in Linux kernel before 2.6.14.1 allows local users to cause a denial of service (kernel oops) and possibly execute code by opening an interface file in /proc/sys/net/ipv4/conf/, waiting until the interface is unregistered, then obtaining and modifying function pointers in memory that was used for the ctl_table.