Red Hat Security Advisory: kernel security and bug fix update

Moderate

Use-after-free vulnerability in the snd_pcm_info() function in the ALSA subsystem in the Linux kernel allows attackers to induce a kernel memory corruption and possibly crash or lock up a system. Due to the nature of the flaw, a privilege escalation cannot be fully ruled out, although we believe it is unlikely.

CWE-416 - Use After Free

A race condition was found in the Linux kernel before version 4.11-rc1 in 'fs/timerfd.c' file which allows a local user to cause a kernel list corruption or use-after-free via simultaneous operations with a file descriptor which leverage improper 'might_cancel' queuing. An unprivileged local user could use this flaw to cause a denial of service of the system. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is unlikely.

CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

A flaw was found in the way Linux kernel KVM hypervisor emulated instructions such as sgdt/sidt/fxsave/fxrstor. It did not check current privilege(CPL) level while emulating unprivileged instructions. An unprivileged guest user/process could use this flaw to potentially escalate privileges inside guest.

CWE-250 - Execution with Unnecessary Privileges