RE: CDE libDtHelp LOGNAME Buffer Overflow Vulnerability

["Thor Larholm" <tlarholm@xxxxxxxx>]

Hi Sunil,

Did iDefense stop posting vulnerabilities to Bugtraq as a matter of
policy or has it just been an error?

I can understand the business motivations for you to restrict
information sharing, though I might disagree.

Regards

Thor Larholm
Senior Security Researcher
PivX Solutions
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Newport Beach, CA 92660
http://www.pivx.com
thor@xxxxxxxx
Stock symbol: (PIVX.OB)
Phone: +1 (949) 231-8496
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-----Original Message-----
From: Jrme" ATHIAS [mailto:jerome.athias@xxxxxxxxxxxx] 
Sent: Wednesday, August 25, 2004 12:23 PM
To: bugtraq@xxxxxxxxxxxxxxxxx
Subject: CDE libDtHelp LOGNAME Buffer Overflow Vulnerability



i dont know if iDEFENSE will post it out of his mailing-list. so...





CDE libDtHelp LOGNAME Buffer Overflow Vulnerability



iDEFENSE Security Advisory 08.25.04

www.idefense.com/application/poi/display?id=134&type=vulnerabilities

August 25, 2004



I. BACKGROUND



The libDtHelp library is a core component of the Common Desktop

Environment (CDE). It provides the help subsystem used by most CDE

applications.



II. DESCRIPTION



Exploitation of a buffer overflow in the libDtHelp library included with

CDE can allow local attackers to gain root privileges.



The vulnerability specifically exists due to a lack of bounds checking

on the LOGNAME environment variable. Local attackers can specify a long

LOGNAME to trigger a buffer overflow in any application linked with

libDtHelp. The overflow is activated once the help subsystem is accessed

by selecting any option under the Help menu. 



This vulnerability occurs in the same sequence of code as the previously

disclosed DTSEARCHPATH and DTUSERSEARCHPATH vulnerabilities, described

in CAN-2003-0834. However, the LOGNAME environment variable was not

reported as a method of attack in related advisories.



US-CERT Vulnerability Note VU#575804, detailing the original attack

vectors is available at:



http://www.kb.cert.org/vuls/id/575804



III. ANALYSIS



Successful exploitation leads to root level access. CDE is a widely

deployed default desktop environment for UNIX operating systems. 

Depending on the function of the machine, this vulnerability could lead

to exposure of highly sensitive data. The vulnerability is easily

exploitable even when stack protections are enabled, furthering the

impact of exposure.



IV. DETECTION



iDEFENSE has confirmed the existence of this vulnerability in Solaris 8

and Solaris 9 without the patches provided for in Sun Alert 57414.

Hewlett Packard HP-UX, Silicon Graphics, Inc. Irix and SCO Unixware are

also reportedly vulnerable.



V. WORKAROUND



If possible, remove the setuid bit from all applications linked to

libDtHelp. The command 'ldd' will display libraries linked with the

specified executable.



VI. VENDOR RESPONSE



Sun successfully addressed this issue with the patches described in Sun

Alert 57414. Specific vendor advisories addressing CAN-2003-0834 are

available in US-CERT Vulnerability Note VU#575804

(http://www.kb.cert.org/vuls/id/575804).

It is believed that other

vendor patches for CAN-2003-0834 will protect against this new attack

vector.



VII. CVE INFORMATION



The Common Vulnerabilities and Exposures (CVE) project has assigned the

name CAN-2003-0834 to this issue. This is a candidate for inclusion in

the CVE list (http://cve.mitre.org),

which standardizes names for

security problems.



VIII. DISCLOSURE TIMELINE



03/04/2004   Initial vendor contact

             (Opengroup.org)

03/04/2004   iDEFENSE clients notified

03/31/2004   Initial vendor response

             (Opengroup.org - further coordination requested)

04/19/2004   Initial vendor contact

             (Hewlett-Packard, IBM, and Sun Microsystems)

04/19/2004   Initial vendor response (Sun Microsystems)

04/20/2004   Initial vendor response (Hewlett-Packard)

08/25/2004   Public disclosure



IX. CREDIT



iDEFENSE Labs is credited with discovering this vulnerability.



Get paid for vulnerability research

http://www.idefense.com/poi/teams/vcp.jsp



X. LEGAL NOTICES



Copyright (c) 2004 iDEFENSE, Inc.



Permission is granted for the redistribution of this alert

electronically. It may not be edited in any way without the express

written consent of iDEFENSE. If you wish to reprint the whole or any

part of this alert in any other medium other than electronically, please

email customerservice@xxxxxxxxxxxx for permission.



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.



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