[ GLSA 202012-12 ] libass: User-assisted execution of arbitrary code

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Gentoo Linux Security Advisory                           GLSA 202012-12
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                                            https://security.gentoo.org/
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  Severity: Normal
     Title: libass: User-assisted execution of arbitrary code
      Date: December 23, 2020
      Bugs: #746413
        ID: 202012-12

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Synopsis
========

A vulnerability has been found in libass that could allow a remote
attacker to execute arbitrary code.

Background
==========

libass is a portable subtitle renderer for the ASS/SSA (Advanced
Substation Alpha/Substation Alpha) subtitle format.

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

     -------------------------------------------------------------------
      Package              /     Vulnerable     /            Unaffected
     -------------------------------------------------------------------
   1  media-libs/libass            < 0.15.0                  >= 0.15.0

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

It was discovered that libass did not properly handle Advanced
Substation Alpha/Substation Alpha subtitle format files.

Impact
======

A remote attacker could entice a user to process an a specially crafted
subtitle format file using an application linked against libass,
possibly resulting in execution of arbitrary code with the privileges
of the process or a Denial of Service condition.

Workaround
==========

There is no known workaround at this time.

Resolution
==========

All libass users should upgrade to the latest version:

   # emerge --sync
   # emerge --ask --oneshot --verbose ">=media-libs/libass-0.15.0"

References
==========

[ 1 ] CVE-2020-26682
       https://nvd.nist.gov/vuln/detail/CVE-2020-26682

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

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

  https://security.gentoo.org/glsa/202012-12

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 2020 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