Share your story
The central voice for Linux and Open Source security news
Home News Topics Advisories HOWTOs Features Newsletters About Register

Sign up!
EnGarde Community
What is the most important Linux security technology?
Linux Events
Linux User Groups
Link to Us
Security Center
Book Reviews
Security Dictionary
Security Tips
White Papers
Featured Blogs
All About Linux
DanWalsh LiveJournal
Latest Newsletters
Linux Security Week: March 30th, 2015
Linux Advisory Watch: March 27th, 2015
LinuxSecurity Newsletters
Choose Lists:
About our Newsletters
RSS Feeds
Get the LinuxSecurity news you want faster with RSS
Powered By

Red Hat: 2010:0221-04: squid: Low Advisory Print E-mail
User Rating:      How can I rate this item?
Posted by Benjamin D. Thomas   
RedHat Linux An updated squid package that fixes two security issues and several bugs is now available for Red Hat Enterprise Linux 5. The Red Hat Security Response Team has rated this update as having low [More...]
                   Red Hat Security Advisory

Synopsis:          Low: squid security and bug fix update
Advisory ID:       RHSA-2010:0221-04
Product:           Red Hat Enterprise Linux
Advisory URL:
Issue date:        2010-03-30
CVE Names:         CVE-2009-2855 CVE-2010-0308 

1. Summary:

An updated squid package that fixes two security issues and several bugs is
now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having low
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.

2. Relevant releases/architectures:

RHEL Desktop Workstation (v. 5 client) - i386, x86_64
Red Hat Enterprise Linux (v. 5 server) - i386, ia64, ppc, s390x, x86_64

3. Description:

Squid is a high-performance proxy caching server for web clients,
supporting FTP, Gopher, and HTTP data objects.

A flaw was found in the way Squid processed certain external ACL helper
HTTP header fields that contained a delimiter that was not a comma. A
remote attacker could issue a crafted request to the Squid server, causing
excessive CPU use (up to 100%). (CVE-2009-2855)

Note: The CVE-2009-2855 issue only affected non-default configurations that
use an external ACL helper script.

A flaw was found in the way Squid handled truncated DNS replies. A remote
attacker able to send specially-crafted UDP packets to Squid's DNS client
port could trigger an assertion failure in Squid's child process, causing
that child process to exit. (CVE-2010-0308)

This update also fixes the following bugs:

* Squid's init script returns a non-zero value when trying to stop a
stopped service. This is not LSB compliant and can generate difficulties in
cluster environments. This update makes stopping LSB compliant. (BZ#521926)

* Squid is not currently built to support MAC address filtering in ACLs.
This update includes support for MAC address filtering. (BZ#496170)

* Squid is not currently built to support Kerberos negotiate
authentication. This update enables Kerberos authentication. (BZ#516245)

* Squid does not include the port number as part of URIs it constructs when
configured as an accelerator. This results in a 403 error. This update
corrects this behavior. (BZ#538738)

* the error_map feature does not work if the same handling is set also on
the HTTP server that operates in deflate mode. This update fixes this
issue. (BZ#470843)

All users of squid should upgrade to this updated package, which resolves
these issues. After installing this update, the squid service will be
restarted automatically.

4. Solution:

Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at

5. Bugs fixed (

496170 - Add arp filter option
516245 - negotiate support not enabled in squid (for kerberized sso)
518182 - CVE-2009-2855 DoS (100% CPU use) while processing certain external ACL helper HTTP headers
521926 - squid 'stop after stop' is not LSB compliant
538738 - Squid accelerator mode works only if port 80 is opened
556389 - CVE-2010-0308 squid: temporary DoS (assertion failure) triggered by truncated DNS packet (SQUID-2010:1)

6. Package List:

RHEL Desktop Workstation (v. 5 client):




Red Hat Enterprise Linux (v. 5 server):







These packages are GPG signed by Red Hat for security.  Our key and 
details on how to verify the signature are available from

7. References:

8. Contact:

The Red Hat security contact is .  More contact
details at

Copyright 2010 Red Hat, Inc.
< Prev   Next >


Latest Features
Peter Smith Releases Linux Network Security Online
Securing a Linux Web Server
Password guessing with Medusa 2.0
Password guessing as an attack vector
Squid and Digest Authentication
Squid and Basic Authentication
Demystifying the Chinese Hacking Industry: Earning 6 Million a Night
Free Online security course (LearnSIA) - A Call for Help
What You Need to Know About Linux Rootkits
Review: A Practical Guide to Fedora and Red Hat Enterprise Linux - Fifth Edition
Yesterday's Edition
Feds Charged With Stealing Money During Silk Road Investigation
EFF questions US government's software flaw disclosure policy
Hotel Router Vulnerability A Reminder Of Untrusted WiFi Risks
Partner Sponsor

Community | HOWTOs | Blogs | Features | Book Reviews | Networking
 Security Projects |  Latest News |  Newsletters |  SELinux |  Privacy |  Home
 Hardening |   About Us |   Advertise |   Legal Notice |   RSS |   Guardian Digital
(c)Copyright 2015 Guardian Digital, Inc. All rights reserved.