CVE-2021-27135: Critical severity xterm vulnerability

Published Feb 10, 2021
·
Updated

A crash was reported in xterm prior to patch #366 when processing a specially crafted sequence of combining characters. The cause is an out of bounds write, which may be exploitable to cause arbitrary code execution.

https://www.openwall.com/lists/oss-security/2021/02/09/7 https://invisible-island.net/xterm/xterm.log.html

Other sources

xterm before Patch #366 allows remote attackers to execute arbitrary code or cause a denial of service (segmentation fault) via a crafted UTF-8 combining character sequence.

Affected Software

5 affected componentsFixes available
debian/xterm
344-1+deb10u2366-1+deb11u1379-1386-1387-1
redhat/xterm<366
366
invisible-island xterm<366
Debian Debian Linux=9.0
Fedoraproject Fedora=33

Event History

Feb 10, 2021
CVE Published
via MITRE·03:51 PM
Data Sourced
via MITRE·03:51 PM
Description

Frequently Asked Questions

1

What is the severity of CVE-2021-27135?

The severity of CVE-2021-27135 is classified as high due to the potential for arbitrary code execution.

2

How do I fix CVE-2021-27135?

To fix CVE-2021-27135, update xterm to version 366 or later for affected distributions.

3

What systems are affected by CVE-2021-27135?

CVE-2021-27135 affects various versions of xterm on Debian, Red Hat, and Fedora systems.

4

Can CVE-2021-27135 be exploited remotely?

CVE-2021-27135 has the potential for exploitation, but whether it can be exploited remotely depends on the configurations and context of the application.

5

What are the symptoms of exploitation of CVE-2021-27135?

Exploitation of CVE-2021-27135 could result in application crashes or, in a successful scenario, arbitrary code execution on the affected system.

Contact

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