Arch Linux Security Advisory ASA-201610-16

Severity: High
Date : 2016-10-24
CVE-ID : CVE-2016-5195
Package : linux-grsec
Type : privilege escalation
Remote : No
Link : https://wiki.archlinux.org/index.php/CVE

Summary

The package linux-grsec before version 1:4.7.10.r201610222037-1 is
vulnerable to privilege escalation.

Resolution

Upgrade to 1:4.7.10.r201610222037-1.

pacman -Syu “linux-grsec>=1:4.7.10.r201610222037-1”

The problem has been fixed upstream in version 4.7.10.r201610222037.

Workaround

None.

Description

A race condition was found in the way the Linux kernel’s memory
subsystem handled the copy-on-write (COW) breakage of private read-only
memory mappings. An unprivileged local user could use this flaw to gain
write access to otherwise read-only memory mappings and thus increase
their privileges on the system.

Impact

An unprivileged local attacker is able to elevate their privileges on
the system and gain root access.

References

https://bugzilla.redhat.com/show_bug.cgi?id=1384344
https://github.com/dirtycow/dirtycow.github.io/wiki/VulnerabilityDetails
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=19be0eaffa3ac7d8eb6784ad9bdbc7d67ed8e619
https://access.redhat.com/security/cve/CVE-2016-5195