Linux kernel built with the Common Internet File System (CONFIG_CIFS) support along with a feature to access Distributed File Systems (CONFIG_CIFS_DFS_UPCALL), is vulnerable to a memory corruption flaw caused by writing one byte past an allocated memory area. It occurs while mounting a DFS share wherein the server provides DFS referral names of certain length. The memory corruption leads to an unresponsive kernel and subsequent crash resulting in Denial of Service.
An user/program able to mount a file system could use this flaw to crash the kernel resulting in DoS.
This issue does not affect the versions of the kernel package as shipped with Red Hat Enterprise Linux 5, 6 and Red Hat Enterprise MRG 2.