[ GLSA 202504-01 ] XZ Utils: Use after free

--===============2883815405967925658==
Content-Type: text/plain; charset="utf-8"

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Gentoo Linux Security Advisory                           GLSA 202504-01
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
                                           https://security.gentoo.org/
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

 Severity: Normal
    Title: XZ Utils: Use after free
     Date: April 05, 2025
     Bugs: #953086
       ID: 202504-01

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

Synopsis
========

A vulnerability has been discovered in XZ Utils, which could lead to
denial of service.

Background
==========

XZ Utils is free general-purpose data compression software with a high
compression ratio.

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

Package            Vulnerable    Unaffected
-----------------  ------------  ------------
app-arch/xz-utils  < 5.6.4-r1    >= 5.6.4-r1

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

A use-after-free has been discovered in XZ utils. Please review the CVE
identifier referenced below for details.

Impact
======

The multithreaded .xz decoder in liblzma has a bug where invalid input
can at least result in a crash. The effects include heap use after free
and writing to an address based on the null pointer plus an offset.
Applications and libraries that use the lzma_stream_decoder_mt function
are affected.

It's unlikely one can achieve more than a crash if xz is built with PIE
on a 64-bit system especially, as is done in Gentoo by default.

Workaround
==========

There is no known workaround at this time.

Resolution
==========

All XZ utils users should upgrade to the latest version:

  # emerge --sync
  # emerge --ask --oneshot --verbose ">=app-arch/xz-utils-5.6.4-r1"

References
==========

[ 1 ] CVE-2025-31115
      https://nvd.nist.gov/vuln/detail/CVE-2025-31115

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

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

 https://security.gentoo.org/glsa/202504-01

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 2025 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
--===============2883815405967925658==
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature
Content-Disposition: attachment; filename="signature.asc"

-----BEGIN PGP SIGNATURE-----
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=wiPo
-----END PGP SIGNATURE-----

--===============2883815405967925658==--