Gentoo Linux Security Advisory 201701-22 - Gentoo's NGINX ebuilds are vulnerable to privilege escalation due to the way log files are handled. Versions less than 1.10.2-r3 are affected.
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Gentoo Linux Security Advisory GLSA 201701-22
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https://security.gentoo.org/
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Severity: Normal
Title: NGINX: Privilege escalation
Date: January 11, 2017
Bugs: #605008
ID: 201701-22
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Synopsis
========
Gentoo's NGINX ebuilds are vulnerable to privilege escalation due to
the way log files are handled.
Background
==========
nginx is a robust, small, and high performance HTTP and reverse proxy
server.
Affected packages
=================
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Package / Vulnerable / Unaffected
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1 www-servers/nginx < 1.10.2-r3 >= 1.10.2-r3
Description
===========
It was discovered that Gentoo's default NGINX installation applied
similar problematic permissions on "/var/log/nginx" as Debian
(DSA-3701) and is therefore vulnerable to the same attack described in
CVE-2016-1247.
Impact
======
A local attacker, who either is already NGINX's system user or belongs
to NGINX's group, could potentially escalate privileges.
Workaround
==========
Ensure that no untrusted user can create files in directories which are
used by NGINX (or an NGINX vhost) to store log files.
Resolution
==========
All NGINX users should upgrade to the latest ebuild revision:
# emerge --sync
# emerge --ask --oneshot --verbose ">=www-servers/nginx-1.10.2-r3"
References
==========
[ 1 ] CVE-2016-1247
http://nvd.nist.gov/nvd.cfm?cvename=CVE-2016-1247
[ 2 ] DSA-3701
https://www.debian.org/security/2016/dsa-3701
[ 3 ] Technical analysis
https://legalhackers.com/advisories/Nginx-Exploit-Deb-Root-PrivEsc-=
CVE-2016-1247.html
Availability
============
This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:
https://security.gentoo.org/glsa/201701-22
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 2017 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.
http://creativecommons.org/licenses/by-sa/2.5