[ GLSA 200410-15 ] Squid: Remote DoS vulnerability

[GLSA]

Gentoo Linux Security Advisory

Title: Squid: Remote DoS vulnerability (GLSA 200410-15)
Severity: normal
Exploitable: remote
Date: October 18, 2004
Updated: December 30, 2007
Bug(s): #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: net-proxy/squid
Vulnerable: < 2.5.7
Unaffected: >= 2.5.7
Architectures: All supported architectures


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: