Gentoo Linux Security Advisory GLSA 200410-15
Severity: Normal
Title: Squid: Remote DoS vulnerability
Date: October 18, 2004
Bugs: #67167
ID: 200410-15
Synopsis
Squid contains a vulnerability in the SNMP module which may lead
to a denial of service.
Background
Squid is a full-featured Web proxy cache designed to run on Unix
systems. It supports proxying and caching of HTTP, FTP, and other
URLs, as well as SSL support, cache hierarchies, transparent
caching, access control lists and many other features.
Affected packages
| Package | Vulnerable | Unaffected |
| 1 www-proxy/squid | < 2.5.7 | >=3D 2.5.7 |
Description
A parsing error exists in the SNMP module of Squid where a
specially-crafted UDP packet can potentially cause the server to
restart, closing all current connections. This vulnerability only
exists in versions of Squid compiled with the ‘snmp’ USE flag.
Impact
An attacker can repeatedly send these malicious UDP packets to
the Squid server, leading to a denial of service.
Workaround
Disable SNMP support or filter the port that has SNMP processing
(default is 3401) to allow only SNMP data from trusted hosts.
To disable SNMP support put the entry snmp_port 0 in the
squid.conf configuration file.
To allow only the local interface to process SNMP, add the entry
“snmp_incoming_address 127.0.0.1” in the squid.conf configuration
file.
Resolution
All Squid users should upgrade to the latest version:
# emerge sync
# emerge -pv ">=3Dwww-proxy/squid-2.5.7"
# emerge ">=3Dwww-proxy/squid-2.5.7"
References
[ 1 ] iDEFENSE Advisory
http://www.idefense.com/application/poi/display?id=3D152&type=3Dvulnerabilities&flashstatus=3Dtrue
Availability
This GLSA and any updates to it are available for viewing at the
Gentoo Security Website:
http://security.gentoo.org/glsa/glsa-200410-15.xml
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 http://bugs.gentoo.org.
License
Copyright 2004 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.