RHSA-2005:060 - Security Advisory

Topic

An updated Squid package that fixes several security issues is now available.

This update has been rated as having important security impact by the Red Hat
Security Response Team.

Description

Squid is a full-featured Web proxy cache.

A buffer overflow flaw was found in the Gopher relay parser. This bug
could allow a remote Gopher server to crash the Squid proxy that reads data
from it. Although Gopher servers are now quite rare, a malicious webpage
(for example) could redirect or contain a frame pointing to an attacker's
malicious gopher server. The Common Vulnerabilities and Exposures project
(cve.mitre.org) has assigned the name CAN-2005-0094 to this issue.

An integer overflow flaw was found in the WCCP message parser. It is
possible to crash the Squid server if an attacker is able to send a
malformed WCCP message with a spoofed source address matching Squid's
"home router". The Common Vulnerabilities and Exposures project
(cve.mitre.org) has assigned the name CAN-2005-0095 to this issue.

A memory leak was found in the NTLM fakeauth_auth helper. It is possible
that an attacker could place the Squid server under high load, causing the
NTML fakeauth_auth helper to consume a large amount of memory, resulting in
a denial of service. The Common Vulnerabilities and Exposures project
(cve.mitre.org) has assigned the name CAN-2005-0096 to this issue.

A NULL pointer de-reference bug was found in the NTLM fakeauth_auth helper.
It is possible for an attacker to send a malformed NTLM type 3 message,
causing the Squid server to crash. The Common Vulnerabilities and
Exposures project (cve.mitre.org) has assigned the name CAN-2005-0097 to
this issue.

A username validation bug was found in squid_ldap_auth. It is possible for
a username to be padded with spaces, which could allow a user to bypass
explicit access control rules or confuse accounting. The Common
Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name
CAN-2005-0173 to this issue.

The way Squid handles HTTP responses was found to need strengthening. It is
possible that a malicious Web server could send a series of HTTP responses
in such a way that the Squid cache could be poisoned, presenting users with
incorrect webpages. The Common Vulnerabilities and Exposures project
(cve.mitre.org) has assigned the names CAN-2005-0174 and CAN-2005-0175 to
these issues.

A bug was found in the way Squid handled oversized HTTP response headers.
It is possible that a malicious Web server could send a specially crafted
HTTP header which could cause the Squid cache to be poisoned, presenting
users with incorrect webpages. The Common Vulnerabilities and Exposures
project (cve.mitre.org) has assigned the name CAN-2005-0241 to this issue.

A buffer overflow bug was found in the WCCP message parser. It is possible
that an attacker could send a malformed WCCP message which could crash the
Squid server or execute arbitrary code. The Common Vulnerabilities and
Exposures project (cve.mitre.org) has assigned the name CAN-2005-0211
to this issue.

Users of Squid should upgrade to this updated package, which contains
backported patches, and is not vulnerable to these issues.

Solution

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied. Use Red Hat
Network to download and update your packages. To launch the Red Hat
Update Agent, use the following command:

up2date

For information on how to install packages manually, refer to the
following Web page for the System Administration or Customization
guide specific to your system:

http://www.redhat.com/docs/manuals/enterprise/

Affected Products

• Red Hat Enterprise Linux Server 4 x86_64
• Red Hat Enterprise Linux Server 4 ia64
• Red Hat Enterprise Linux Server 4 i386
• Red Hat Enterprise Linux Workstation 4 x86_64
• Red Hat Enterprise Linux Workstation 4 ia64
• Red Hat Enterprise Linux Workstation 4 i386
• Red Hat Enterprise Linux Desktop 4 x86_64
• Red Hat Enterprise Linux Desktop 4 i386
• Red Hat Enterprise Linux for IBM z Systems 4 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390
• Red Hat Enterprise Linux for Power, big endian 4 ppc

Fixes

• BZ - 145545 - CAN-2005-0094 Multiple issues with squid (CAN-2005-0095 CAN-2005-0096 CAN-2005-0097)
• BZ - 146161 - CAN-2005-0173 Multiple squid issues (CAN-2005-0174 CAN-2005-0175)
• BZ - 146779 - CAN-2005-0211 Buffer overflow in WCCP recvfrom() call
• BZ - 146785 - CAN-2005-0241 Correct handling of oversized reply headers

CVEs

• CVE-2005-0094
• CVE-2005-0095
• CVE-2005-0096
• CVE-2005-0097
• CVE-2005-0173
• CVE-2005-0174
• CVE-2005-0175
• CVE-2005-0211
• CVE-2005-0241

References

• http://www.squid-cache.org/Advisories/SQUID-2005_1.txt
• http://www.squid-cache.org/Advisories/SQUID-2005_2.txt
• http://www.squid-cache.org/Advisories/SQUID-2005_3.txt
• http://www.squid-cache.org/Versions/v2/2.5/bugs/#squid-2.5.STABLE7-fakeauth_auth
• http://www.squid-cache.org/Versions/v2/2.5/bugs/#squid-2.5.STABLE7-ldap_spaces