USN-3717-1: PolicyKit vulnerabilities

16 July 2018

policykit-1 vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 18.04 LTS
  • Ubuntu 17.10
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 LTS

Summary

Several security issues were fixed in PolicyKit.

Software Description

  • policykit-1 - framework for managing administrative policies and privileges

Details

Tavis Ormandy discovered that PolicyKit incorrectly handled certain invalid object paths. A local attacker could possibly use this issue to cause PolicyKit to crash, resulting in a denial of service. This issue only affected Ubuntu 14.04 LTS. (CVE-2015-3218)

It was discovered that PolicyKit incorrectly handled certain duplicate action IDs. A local attacker could use this issue to cause PolicyKit to crash, resulting in a denial of service, or possibly escalate privileges. This issue only affected Ubuntu 14.04 LTS. (CVE-2015-3255)

Tavis Ormandy discovered that PolicyKit incorrectly handled duplicate cookie values. A local attacker could use this issue to cause PolicyKit to crash, resulting in a denial of service, or possibly escalate privileges. This issue only affected Ubuntu 14.04 LTS. (CVE-2015-4625)

Matthias Gerstner discovered that PolicyKit incorrectly checked users. A local attacker could possibly use this issue to cause authentication dialogs to show up for other users, leading to a denial of service or an information leak. (CVE-2018-1116)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 18.04 LTS
libpolkit-backend-1-0 - 0.105-20ubuntu0.18.04.1
Ubuntu 17.10
libpolkit-backend-1-0 - 0.105-18ubuntu0.1
Ubuntu 16.04 LTS
libpolkit-backend-1-0 - 0.105-14.1ubuntu0.1
Ubuntu 14.04 LTS
libpolkit-backend-1-0 - 0.105-4ubuntu3.14.04.2

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

After a standard system update you need to reboot your computer to make all the necessary changes.

References