Gentoo: GLSA-202101-38: NSD: Symbolic link traversal

Date 28 Jan 2021

Category Gentoo Linux Distribution - Security Advisories

210

Posted By LinuxSecurity Advisories

A vulnerability was discovered in NSD which could allow a local attacker to cause a Denial of Service condition.

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Gentoo Linux Security Advisory                           GLSA 202101-38
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                                           https://security.gentoo.org/
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 Severity: Normal
    Title: NSD: Symbolic link traversal
     Date: January 29, 2021
     Bugs: #758977
       ID: 202101-38

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Synopsis
========

A vulnerability was discovered in NSD which could allow a local
attacker to cause a Denial of Service condition.

Background
==========

An authoritative only, high performance, open source name server

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

    -------------------------------------------------------------------
     Package              /     Vulnerable     /            Unaffected
    -------------------------------------------------------------------
  1  net-dns/nsd                  < 4.3.4                    >= 4.3.4

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

A local vulnerability was discovered that would allow for a local
symlink attack due to how NSD handles PID files.

Impact
======

A local attacker could cause a Denial of Service condition.

Workaround
==========

There is no known workaround at this time.

Resolution
==========

All NSD users should upgrade to the latest version:

  # emerge --sync
  # emerge --ask --oneshot --verbose ">=net-dns/nsd-4.3.4"

References
==========

[ 1 ] CVE-2020-28935
      https://nvd.nist.gov/vuln/detail/CVE-2020-28935
[ 2 ] Upstream advisory
      https://www.nlnetlabs.nl/downloads/nsd/CVE-2020-28935.txt

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

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

 https://security.gentoo.org/glsa/202101-38

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
This email address is being protected from spambots. You need JavaScript enabled to view it. 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