[gentoo-announce] [ GLSA 200901-03 ] pdnsd: Denial of Service and cache poisoning

[news 28]

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Gentoo Linux Security Advisory GLSA 200901-03

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http://security.gentoo.org/

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Severity: Normal

Title: pdnsd: Denial of Service and cache poisoning

Date: January 11, 2009

Bugs: #231285

ID: 200901-03

 

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Synopsis

========

 

Two errors in pdnsd allow for Denial of Service and cache poisoning.

 

Background

==========

 

pdnsd is a proxy DNS server with permanent caching that is designed to

cope with unreachable DNS servers.

 

Affected packages

=================

 

-------------------------------------------------------------------

Package / Vulnerable / Unaffected

-------------------------------------------------------------------

1 net-dns/pdnsd < 1.2.7 >= 1.2.7

 

Description

===========

 

Two issues have been reported in pdnsd:

 

* The p_exec_query() function in src/dns_query.c does not properly

handle many entries in the answer section of a DNS reply, related to

a "dangling pointer bug" (CVE-2008-4194).

 

* The default value for query_port_start was set to 0, disabling UDP

source port randomization for outgoing queries (CVE-2008-1447).

 

Impact

======

 

An attacker could exploit the second weakness to poison the cache of

pdnsd and thus spoof DNS traffic, which could e.g. lead to the

redirection of web or mail traffic to malicious sites. The first issue

can be exploited by enticing pdnsd to send a query to a malicious DNS

server, or using the port randomization weakness, and might lead to a

Denial of Service.

 

Workaround

==========

 

Port randomization can be enabled by setting the "query_port_start"

option to 1024 which would resolve the CVE-2008-1447 issue.

 

Resolution

==========

 

All pdnsd users should upgrade to the latest version:

 

# emerge --sync

# emerge --ask --oneshot --verbose ">=net-dns/pdnsd-1.2.7"

 

References

==========

 

[ 1 ] CVE-2008-1447

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-1447

[ 2 ] CVE-2008-4194

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-4194

 

Availability

============

 

This GLSA and any updates to it are available for viewing at

the Gentoo Security Website:

 

http://security.gentoo.org/glsa/glsa-200901-03.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 ( -at -) gentoo.org or alternatively, you may file a bug at

http://bugs.gentoo.org.

 

License

=======

 

Copyright 2009 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.

 

http://creativecommons.org/licenses/by-sa/2.5