Ubuntu Security Notice USN-3717-2

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Ubuntu Security Notice USN-3717-2
July 17, 2018

policykit-1 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

– Ubuntu 12.04 ESM

Summary:

Several security issues were fixed in PolicyKit.

Software Description:
– policykit-1: framework for managing administrative policies and
privileges

Details:

USN-3717-1 fixed a vulnerability in PolicyKit. This update provides
the corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

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. (CVE-2015-3255)

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 12.04 ESM:
libpolkit-backend-1-0 0.104-1ubuntu1.2

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

References:
https://usn.ubuntu.com/usn/usn-3717-2
https://usn.ubuntu.com/usn/usn-3717-1
CVE-2015-3255, CVE-2018-1116