CVE-2016-2568

Name: CVE-2016-2568
Creator: NVD / NIST
Published: 2017-02-13T18:59:00.393+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.8/10EPSS 0.35%

Last modified Jun 17, 2026

CVE-2016-2568 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. pkexec, when used with --user nonpriv, allows local users to escape to the parent session via a crafted TIOCSTI ioctl call, which pushes characters to the terminal's input buffer.. EPSS estimates a 0.35% chance of exploitation in the next 30 days.

Description

pkexec, when used with --user nonpriv, allows local users to escape to the parent session via a crafted TIOCSTI ioctl call, which pushes characters to the terminal's input buffer.

Metrics

CVSS 3.1

7.8/10

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS Probability

0.35%

26.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-116

Affected Software

Vendor	Product	Versions
Freedesktop	Polkit	All versions
Redhat	Enterprise Linux	6.0
Redhat	Enterprise Linux	7.0

References

http://www.openwall.com/lists/oss-security/2016/02/26/3Mailing List, Third Party Advisory
https://access.redhat.com/security/cve/cve-2016-2568Third Party Advisory
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=816062Mailing List, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1300746Issue Tracking, Third Party Advisory
https://ubuntu.com/security/CVE-2016-2568Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/02/26/3Mailing List, Third Party Advisory
https://access.redhat.com/security/cve/cve-2016-2568Third Party Advisory
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=816062Mailing List, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1300746Issue Tracking, Third Party Advisory
https://ubuntu.com/security/CVE-2016-2568Third Party Advisory

Timeline

Published: Feb 13, 2017
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2016-2568?

pkexec, when used with --user nonpriv, allows local users to escape to the parent session via a crafted TIOCSTI ioctl call, which pushes characters to the terminal's input buffer.

How severe is CVE-2016-2568?

CVE-2016-2568 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.35% probability of exploitation in the next 30 days.

How do I fix CVE-2016-2568?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2016-2568?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST