Amazon Linux AMI Security Advisory: ALAS-2011-22
Advisory Release Date: 2011-11-19 01:22 Pacific
Advisory Updated Date: 2014-09-14 14:50 Pacific
The epoll implementation in the Linux kernel 188.8.131.52 and earlier does not properly traverse a tree of epoll file descriptors, which allows local users to cause a denial of service (CPU consumption) via a crafted application that makes epoll_create and epoll_ctl system calls.
Buffer overflow in the xfs_readlink function in fs/xfs/xfs_vnodeops.c in XFS in the Linux kernel 2.6, when CONFIG_XFS_DEBUG is disabled, allows local users to cause a denial of service (memory corruption and crash) and possibly execute arbitrary code via an XFS image containing a symbolic link with a long pathname.
crypto/ghash-generic.c in the Linux kernel before 3.1 allows local users to cause a denial of service (NULL pointer dereference and OOPS) or possibly have unspecified other impact by triggering a failed or missing ghash_setkey function call, followed by a (1) ghash_update function call or (2) ghash_final function call, as demonstrated by a write operation on an AF_ALG socket.
Run yum update kernel to update your system. You will need to reboot your system in order for the new kernel to be running.