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Gentoo Linux Security Advisory                           GLSA 202003-45
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                                           https://security.gentoo.org/
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 Severity: High
    Title: PyYAML: Arbitrary code execution
     Date: March 19, 2020
     Bugs: #659348
       ID: 202003-45

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Synopsis
=======
A flaw in PyYAML might allow attackers to execute arbitrary code.

Background
=========
PyYAML is a YAML parser and emitter for Python.

Affected packages
================
    -------------------------------------------------------------------
     Package              /     Vulnerable     /            Unaffected
    -------------------------------------------------------------------
  1  dev-python/pyyaml             < 5.1                       >= 5.1

Description
==========
It was found that using yaml.load() API on untrusted input could lead
to arbitrary code execution.

Impact
=====
A remote attacker could entice a user to process specially crafted
input in an application using yaml.load() from PyYAML, 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 PyYAML users should upgrade to the latest version:

  # emerge --sync
  # emerge --ask --oneshot --verbose ">=dev-python/pyyaml-5.1"

References
=========
[ 1 ] CVE-2017-18342
      https://nvd.nist.gov/vuln/detail/CVE-2017-18342

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

 https://security.gentoo.org/glsa/202003-45

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
security@gentoo.org 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/