CVE-2016-2568: High severity Freedesktop polkit vulnerability

Published Jan 21, 2016
·
Updated

It was reported that when executing a program via "pkexec --user nonpriv program", the nonpriv session can escape to the parent session by using the TIOCSTI ioctl to push characters into the terminal's input buffer, allowing privilege escalation.

Original bug report (contains reproducer):

https://bugzilla.redhat.com/showbug.cgi?id=1299955

Other sources

pkexec, when used with --user nonpriv, allows local users to escape to the parent session

Microsoft

Affected Software

7 affected componentsFixes available
Freedesktop polkit
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
debian/policykit-1<=0.105-31+deb11u1, <=0.105-31+deb11u2, <=122-3
126-2127-3
Microsoft cbl2 polkit 0.119-3<0.119-3
0.119-3
Microsoft azl3 polkit 123-1<123-1
123-1
Microsoft cm1 polkit 0.116-7<0.116-7
0.116-7

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/policykit-1 to a version that resolves this vulnerability.

    Fixed in 126-2Fixed in 127-3
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 123-1
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 0.119-3
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 0.116-7

Event History

Jan 21, 2016
Data Sourced
via Red Hat·03:42 PM
DescriptionSeverityAffected Software
Feb 27, 2016
Data Sourced
via Debian·05:33 AM
SeverityAffected Software
Feb 13, 2017
CVE Published
via MITRE·06:00 PM
Data Sourced
via MITRE·06:00 PM
Description
Data Sourced
via NVD·06:59 PM
DescriptionSeverityWeaknessAffected Software
Aug 5, 2024
Data Sourced
via Launchpad·11:41 PM
Description
Oct 2, 2025
Data Sourced
via Microsoft·06:10 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·06:10 AM
Affected Software
Updated
via Microsoft·06:10 AM
Affected Software
Updated
via Microsoft·06:10 AM
SeverityAffected Software
Updated
via Microsoft·06:10 AM
DescriptionSeverity
Feb 19, 2026
Data Sourced
via Ubuntu·04:46 PM
RemedyDescriptionSeverityAffected Software
May 13, 2026
Data Sourced
via Debian·03:19 AM
Description
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Frequently Asked Questions

1

What is the severity of CVE-2016-2568?

CVE-2016-2568 is considered a high severity vulnerability due to its potential to allow privilege escalation.

2

How do I fix CVE-2016-2568?

To fix CVE-2016-2568, update the affected packages in your operating system to the latest versions that have addressed this vulnerability.

3

Which systems are affected by CVE-2016-2568?

CVE-2016-2568 affects systems utilizing policykit-1 and applications that make use of the TIOCSTI ioctl.

4

What could happen if CVE-2016-2568 is exploited?

If exploited, CVE-2016-2568 allows an unprivileged user to escalate their privileges to execute commands with higher permissions.

5

When was CVE-2016-2568 reported?

CVE-2016-2568 was reported in February 2016, raising concerns about the security of systems using affected software.

Contact

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