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SYNTHESIS OF THE VULNERABILITY

A local attacker can create a process which blocks some kernel
threads, in order to create a denial of service.

Severity : 1/4

Creation date : 22/12/2011

IMPACTED PRODUCTS

– Linux kernel

DESCRIPTION OF THE VULNERABILITY

The Linux kernel has several tasks/threads. The Scheduler splits
the execution time between these tasks.

An attacker can create a process which sets the skip_clock_update
variable. The Scheduler ignores its execution time, so the process
can consume a lot of CPU resources.

A local attacker can therefore create a process which blocks some
kernel threads, in order to create a denial of service.

ACCESS TO THE COMPLETE VIGIL@NCE BULLETIN

http://vigilance.fr/vulnerability/Linux-kernel-denial-of-service-via-skip-clock-update-11245