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Gentoo: GLSA-201701-22 NGINX Privilege Escalation Risk Specification

gentoo
Calendar Grey January 11, 2017
Scroller Gentoo
The ebuilds for NGINX in Gentoo encounter a standard risk of privilege escalation. It is advisable to upgrade for enhanced security measures.
Gentoo's NGINX ebuilds are vulnerable to privilege escalation due to the way log files are handled.

Summary

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.

Topics%20covered

Topics Covered

security advisory gentoo software update privilege escalation local attack nginx normal severity

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://lists.debian.org/debian-security-announce/2016/msg00281.html [ 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
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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.

Severity: Normal
Title: NGINX: Privilege escalation
Date: January 11, 2017
Bugs: #605008
ID: 201701-22

Topics%20covered

Topics Covered

security advisory gentoo software update privilege escalation local attack nginx normal severity

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.

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Affected Packages

------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 www-servers/nginx < 1.10.2-r3 >= 1.10.2-r3

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.