CVE-2016-5195

Published: 19 October 2016

Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect handling of a copy-on-write (COW) feature to write to a read-only memory mapping, as exploited in the wild in October 2016, aka "Dirty COW."

From the Ubuntu Security Team

It was discovered that a race condition existed in the memory manager of the Linux kernel when handling copy-on-write breakage of private read-only memory mappings. A local attacker could use this to gain administrative privileges.

Notes

android kernels (flo, goldfish, grouper, maguro, mako and manta) are
not supported on the Ubuntu Touch 14.10 and earlier preview kernels
linux-lts-saucy no longer receives official support
linux-lts-quantal no longer receives official support

Status

Severity score breakdown

References

• https://ubuntu.com/security/notices/USN-3107-1
• https://ubuntu.com/security/notices/USN-3106-4
• https://ubuntu.com/security/notices/USN-3106-3
• https://ubuntu.com/security/notices/USN-3106-2
• https://ubuntu.com/security/notices/USN-3106-1
• https://ubuntu.com/security/notices/USN-3105-2
• https://ubuntu.com/security/notices/USN-3105-1
• https://ubuntu.com/security/notices/USN-3104-1
• https://ubuntu.com/security/notices/USN-3107-2
• https://ubuntu.com/security/notices/USN-3104-2
• https://www.cve.org/CVERecord?id=CVE-2016-5195
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog
• NVD
• Launchpad
• Debian

Bugs

• https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1633547