[ GLSA 200406-21 ] mit-krb5: Multiple buffer overflows

[pahud]

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Gentoo Linux Security Advisory GLSA 200406-21
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http://security.gentoo.org/
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Severity: High
Title: mit-krb5: Multiple buffer overflows in
krb5_aname_to_localname
Date: June 29, 2004
Bugs: #52744
ID: 200406-21

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Synopsis
========

mit-krb5 contains multiple buffer overflows in the function
krb5_aname_to_localname(). This could potentially lead to a complete
remote system compromise.

Background
==========

mit-krb5 is the free implementation of the Kerberos network
authentication protocol by the Massachusetts Institute of Technology.

Affected packages
=================

-------------------------------------------------------------------
Package / Vulnerable / Unaffected
-------------------------------------------------------------------
1 app-crypt/mit-krb5 <= 1.3.3 >= 1.3.3-r1

Description
===========

The library function krb5_aname_to_localname() contains multiple buffer
overflows. This is only exploitable if explicit mapping or rules-based
mapping is enabled. These are not enabled as default.

With explicit mapping enabled, an attacker must authenticate using a
principal name listed in the explicit mapping list.

With rules-based mapping enabled, an attacker must first be able to
create arbitrary principal names either in the local realm Kerberos
realm or in a remote realm from which the local realm's service are
reachable by cross-realm authentication.

Impact
======

An attacker could use these vulnerabilities to execute arbitrary code
with the permissions of the user running mit-krb5, which could be the
root user.

Workaround
==========

There is no known workaround at this time. All users are encouraged to
upgrade to the latest available version.

Resolution
==========

mit-krb5 users should upgrade to the latest version:

# emerge sync

# emerge -pv ">=app-crypt/mit-krb5-1.3.3-r1"
# emerge ">=app-crypt/mit-krb5-1.3.3-r1"

References
==========

[ 1 ] CAN-2004-0523
http://cve.mitre.org/cgi-bin/cvename.cg ... -2004-0523
[ 2 ] MIT krb5 Security Advisory
http://web.mit.edu/kerberos/advisories/ ... _to_ln.txt

Availability
============

This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

http://security.gentoo.org/glsa/glsa-200406-21.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@gentoo.org or alternatively, you may file a bug at
http://bugs.gentoo.org.

License
=======

Copyright 2004 Gentoo Technologies, 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/1.0