Computer Associates License Client and Server Invalid Command Buffer
Overflow

iDEFENSE Security Advisory 03.02.05
www.idefense.com/application/poi/display?id=210&type=vulnerabilities
March 2, 2005

I. BACKGROUND

The Computer Associates License Client/Server applications provide a 
method for CA products to register their licenses on the network. The 
License Client and Server are distributed with almost all CA software 
distributions. More information about Computer Associates software 
products is available from:

   http://www3.ca.com/Products/

II. DESCRIPTION

Remote exploitation of a buffer overflow vulnerability in Computer 
Associates International Inc. License Server and License Client can 
allow attackers to execute arbitrary code.

The vulnerability specifically exists because of insufficient bounds 
checking on user-supplied values in requests with an invalid format. 
When a packet containing an overly long string which is not a valid 
command is received, the server uses that string to generate a log 
message without checking if the buffer that the message is being stored
in is large  enough. By sending a string over 2100 bytes long, it is
possible to  overwrite the saved instruction pointer, allowing execution
of arbitrary code.

III. ANALYSIS

Exploitation allows remote attackers to execute arbitrary code under the
privileges of Local System (on Windows platforms) or root (on Linux 
platforms). The CA License Server does not run by default, but is 
packaged with most Computer Associates software distributions. The CA 
License Client does run by default and is packaged with almost all CA 
software.

IV. DETECTION

iDEFENSE has confirmed that CA License Server 0.1.0.15 and CA License 
Client 0.1.0.15 are vulnerable. It is suspected that most CA products 
are running vulnerable versions of the client and/or server.

V. WORKAROUND

Use a firewall to only allow trusted hosts to connect to the Computer 
Associates License Server and Client ports.

VI. VENDOR RESPONSE

A vendor advisory for this issue is available at:

http://supportconnectw.ca.com/public/ca_common_docs/security_notice.asp

Patches for this issue are available at:

http://supportconnectw.ca.com/public/reglic/downloads/licensepatch.asp#a
lp

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CAN-2005-0581 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org), which standardizes names for
security problems. This is one of several overflows that have been
assigned CAN-2005-0581.

VIII. DISCLOSURE TIMELINE

02/08/2005  Initial vendor notification
02/09/2005  Initial vendor response
03/02/2005  Coordinated public disclosure

IX. CREDIT

This vulnerability was discovered by Greg MacManus, iDEFENSE Labs.

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X. LEGAL NOTICES

Copyright (c) 2005 iDEFENSE, Inc.

Permission is granted for the redistribution of this alert
electronically. It may not be edited in any way without the express
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part of this alert in any other medium other than electronically, please
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Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct, indirect,
or consequential loss or damage arising from use of, or reliance on,
this information.