Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
===========================================================================
AUSCERT External Security Bulletin Redistribution
ESB-2010.0799
Squid Proxy Cache Security Update Advisory SQUID-2010:3
7 September 2010
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: Squid 3.0 through 3.0.STABLE25
Squid 3.1 through 3.1.7
Squid 3.2 through 3.2.0.1
Publisher: Squid
Operating System: Windows
UNIX variants (UNIX, Linux, OSX)
Impact/Access: Denial of Service -- Remote/Unauthenticated
Resolution: Patch/Upgrade
Original Bulletin:
http://www.squid-cache.org/Advisories/SQUID-2010_3.txt
- --------------------------BEGIN INCLUDED TEXT--------------------
__________________________________________________________________
Squid Proxy Cache Security Update Advisory SQUID-2010:3
__________________________________________________________________
Advisory ID: SQUID-2010:3
Date: September 03, 2010
Summary: Denial of service in request processing
Affected versions: Squid 3.0 -> 3.0.STABLE25
Squid 3.1 -> 3.1.7
Squid 3.2 -> 3.2.0.1
Fixed in version: Squid 3.1.8, 3.2.0.2
__________________________________________________________________
http://www.squid-cache.org/Advisories/SQUID-2010_3.txt
__________________________________________________________________
Problem Description:
Due to an internal error in string handling Squid is vulnerable
to a denial of service attack when processing specially crafted
requests.
__________________________________________________________________
Severity:
This problem allows any trusted client to perform a denial of
service attack on the Squid service.
There are applications already in general public use which can
trigger this problem for 3.1 and 3.2 on occasion without intended
malice.
__________________________________________________________________
Updated Packages:
This bug is fixed by Squid versions 3.1.8 and 3.2.0.2
In addition, patches addressing this problem for stable releases
can be found in our patch archives:
Squid 3.0:
http://www.squid-cache.org/Versions/v3/3.0/changesets/squid-3.0-9189.patch
Squid 3.1:
http://www.squid-cache.org/Versions/v3/3.1/changesets/squid-3.1-10090.patch
If you are using a prepackaged version of Squid then please refer
to the package vendor for availability information on updated
packages.
__________________________________________________________________
Determining if your version is vulnerable:
Squid-3.0:
All Squid-3.0 versions up to and including 3.0.STABLE25 have
some risk of being vulnerable to variations of the problem.
The particular 0-day tests currently known do not trigger it.
Squid-3.1:
All versions up to and including 3.1.7 are at some risk of being
vulnerable to the problem and its variations.
squid.conf containing with "ignore_expect_100 on" are vulnerable
to the known active 0-day.
Binaries built with --disable-http-violations are not vulnerable
to the known active 0-day.
Squid-3.2:
The 3.2.0.1 beta version is vulnerable under the same conditions
as for Squid-3.1.
__________________________________________________________________
Workarounds:
These workarounds apply only to the known active 0-day triggers.
1) Checking that ignore_expect_100 squid.conf option is set to
"off" (the default), or removed completely from squid.conf.
or,
2) Building Squid with --disable-http-violations.
__________________________________________________________________
Contact details for the Squid project:
For installation / upgrade support on binary packaged versions
of Squid: Your first point of contact should be your binary
package vendor.
If you install and build Squid from the original Squid sources
then the squid-users@squid-cache.org mailing list is your primary
support point. For subscription details see
http://www.squid-cache.org/Support/mailing-lists.html.
For reporting of non-security bugs in the latest release
the squid bugzilla database should be used
http://www.squid-cache.org/bugs/.
For reporting of security sensitive bugs send an email to the
squid-bugs@squid-cache.org mailing list. It's a closed list
(though anyone can post) and security related bug reports are
treated in confidence until the impact has been established.
__________________________________________________________________
Credits:
The vulnerability was discovered by Phil Oester.
__________________________________________________________________
Revision history:
2010-08-30 14:19 GMT Initial Report
2010-09-01 08:04 GMT Patches Released
2010-09-03 09:00 GMT Initial version
__________________________________________________________________
- --------------------------END INCLUDED TEXT--------------------
You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.
NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members. As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.
NOTE: This is only the original release of the security bulletin. It may
not be updated when updates to the original are made. If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.
Contact information for the authors of the original document is included
in the Security Bulletin above. If you have any questions or need further
information, please contact them directly.
Previous advisories and external security bulletins can be retrieved from:
http://www.auscert.org.au/render.html?cid=1980
===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072
Internet Email: auscert@auscert.org.au
Facsimile: (07) 3365 7031
Telephone: (07) 3365 4417 (International: +61 7 3365 4417)
AusCERT personnel answer during Queensland business hours
which are GMT+10:00 (AEST).
On call after hours for member emergencies only.
===========================================================================
-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967
iD4DBQFMhbnI/iFOrG6YcBERAihOAKCyRypjvxtUu7m6z00hTkb3tMb5HACYpjkI
UZUhOgE1JO9ws3cVQC66fA==
=OOW7
-----END PGP SIGNATURE-----