Amazon Linux AMI : kernel (ALAS-2014-455)
High Nessus Plugin ID 79725
SynopsisThe remote Amazon Linux AMI host is missing a security update.
DescriptionThe sctp_process_param function in net/sctp/sm_make_chunk.c in the SCTP implementation in the Linux kernel before 3.17.4, when ASCONF is used, allows remote attackers to cause a denial of service (NULL pointer dereference and system crash) via a malformed INIT chunk.
The pivot_root implementation in fs/namespace.c in the Linux kernel through 3.17 does not properly interact with certain locations of a chroot directory, which allows local users to cause a denial of service (mount-tree loop) via . (dot) values in both arguments to the pivot_root system call. (CVE-2014-7970)
The do_double_fault function in arch/x86/kernel/traps.c in the Linux kernel through 3.17.4 does not properly handle faults associated with the Stack Segment (SS) segment register, which allows local users to cause a denial of service (panic) via a modify_ldt system call, as demonstrated by sigreturn_32 in the linux-clock-tests test suite.
A flaw was found in the way the Linux kernel handled GS segment register base switching when recovering from a #SS (stack segment) fault on an erroneous return to user space. A local, unprivileged user could use this flaw to escalate their privileges on the system.
SolutionRun 'yum clean all' followed by 'yum update kernel' to update your system. You will need to reboot your system in order for the new kernel to be running.