Gentoo: GLSA-202105-11: GNU Screen: User-assisted execution of arbi...

Advisories

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Gentoo Linux Security Advisory                           GLSA 202105-11
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
                                            https://security.gentoo.org/
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  Severity: Normal
     Title: GNU Screen: User-assisted execution of arbitrary code
      Date: May 26, 2021
      Bugs: #769770
        ID: 202105-11

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Synopsis
========

A vulnerability in GNU screen may allow a remote attacker to execute
arbitrary code.

Background
==========

GNU Screen is a full-screen window manager that multiplexes a physical
terminal between several processes, typically interactive shells.

Affected packages
=================

     -------------------------------------------------------------------
      Package              /     Vulnerable     /            Unaffected
     -------------------------------------------------------------------
   1  app-misc/screen             < 4.8.0-r2               >= 4.8.0-r2

Description
===========

It was discovered that GNU screen did not properly handle certain UTF-8
character sequences.

Impact
======

A remote attacker could entice a user to run a program where attacker
controls the output inside a GNU screen session, possibly resulting in
execution of arbitrary code with the privileges of the process or a
Denial of Service condition.

Workaround
==========

This vulnerability can be mitigated by disabling UTF-8 processing in
.screenrc.

Resolution
==========

All GNU screen users should upgrade to the latest version:

   # emerge --sync
   # emerge --ask --oneshot --verbose ">=app-misc/screen-4.8.0-r2"

References
==========

[ 1 ] CVE-2021-26937
       https://nvd.nist.gov/vuln/detail/CVE-2021-26937

Availability
============

This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

  https://security.gentoo.org/glsa/202105-11

Concerns?
=========

Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users' machines is of utmost
importance to us. Any security concerns should be addressed to
[email protected] or alternatively, you may file a bug at
https://bugs.gentoo.org.

License
=======

Copyright 2021 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).

The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.

https://creativecommons.org/licenses/by-sa/2.5

Gentoo: GLSA-202105-11: GNU Screen: User-assisted execution of arbitrary code

Summary

It was discovered that GNU screen did not properly handle certain UTF-8 character sequences.

Resolution

All GNU screen users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=app-misc/screen-4.8.0-r2"

References

[ 1 ] CVE-2021-26937 https://nvd.nist.gov/vuln/detail/CVE-2021-26937

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website:
https://security.gentoo.org/glsa/202105-11

Concerns

Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users' machines is of utmost importance to us. Any security concerns should be addressed to [email protected] or alternatively, you may file a bug at https://bugs.gentoo.org.

Severity
Severity: Normal
Title: GNU Screen: User-assisted execution of arbitrary code
Issued Date: May 26, 2021
Bugs: #769770
ID: 202105-11

Synopsis

A vulnerability in GNU screen may allow a remote attacker to execute arbitrary code.

Background

GNU Screen is a full-screen window manager that multiplexes a physical terminal between several processes, typically interactive shells.

Affected Packages

------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 app-misc/screen < 4.8.0-r2 >= 4.8.0-r2

Impact

A remote attacker could entice a user to run a program where attacker controls the output inside a GNU screen session, possibly resulting in execution of arbitrary code with the privileges of the process or a Denial of Service condition.

Workaround

This vulnerability can be mitigated by disabling UTF-8 processing in .screenrc.

We use cookies to provide and improve our services. By using our site, you consent to our Cookie Policy.