I. BACKGROUND
The UnixWare setuid root applications /usr/X/bin/Launch_Application
and /usr/X/bin/Remote_Apps are vulnerable to a local buffer overflow.
NetWare_Access and App_Sharing are also vulnerable, they are not
installed setuid but get root privs from /etc/security/tbc/privs.
II. DESCRIPTION
The overflow occurs when the HOME environment variable is too long. The
overflow enables local users to take control over the program and
execute arbitrary code as root.
III. ANALYSIS
An exploit has been developed and tested on UnixWare 7.0.1. According to
http://docsrv.caldera.com/FEATS/new_features_710a_network.html both
Launch_Application and Remote_Apps have been removed from UnixWare 7.1.1
and later.
IV. DETECTION
HOME=`perl -e 'print "x"x10000'`;export HOME;Launch_Application
A crash indicates that the system is vulnerable.
V. WORKAROUND
Remove the suid bits from Launch_Application and Remote_Apps.
Use the filepriv command to revoke the extra privs from
NetWare_Access and App_Sharing.
VI. CVE INFORMATION
A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not
been assigned yet.
VII. DISCLOSURE TIMELINE
02/11/2003 Initial vendor notification
02/11/2003 Initial vendor response
02/25/2003 Public Disclosure
VIII. CREDIT
Texonet Co. is credited with this discovery.
Get paid for vulnerability research
http://www.idefense.com/poi/teams/vcp.jsp
IX. LEGAL NOTICES
Copyright © 2004 iDEFENSE, Inc.
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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,
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