iDefense Security Advisory 03.23.07: DataRescue IDA Pro Remote Debugger Server Authentication Bypass Vulnerability

DataRescue IDA Pro Remote Debugger Server Authentication Bypass
Vulnerability

iDefense Security Advisory 03.23.07
http://labs.idefense.com/intelligence/vulnerabilities/
Mar 23, 2007

I. BACKGROUND

DataRescue Inc.'s IDA Pro is a disassembler and debugger for Windows, Linux,
or Macintosh. It supports multiple binary formats as well as many processor
architectures. For more information about IDA Pro, visit the vendor's
website
at the following URL.

http://www.datarescue.com/idabase/index.htm

II. DESCRIPTION

Remote exploitation of a password bypass vulnerability in DataRescue Inc.'s
IDA Pro Remote Debugger Server allows attackers to execute arbitrary code
under the context of the user who is running the remote debugger server.

Since version 4.8, IDA Pro supports remote debugging of x86/AMD64 Windows PE
applications and Linux ELF applications over TCP/IP networks. The IDA
distribution ships with a debugger server for Windows, Linux, and (as of
version 5.1) MacOS X.

The IDA Pro debugger server allows a user to specify a password for
authentication by supplying the -P parameter. The vulnerability specifically
exists in the the processor_request() function. This function is used
for the
initial packet exchange as well as subsequent requests. This function
did not
ensure that the remote user has authenticated prior to calling the
perform_request() function. As such, attacker requests sent prior to
authenticating would be processed normally.

III. ANALYSIS

Exploitation of the described vulnerability allows attackers to execute
arbitrary code under the context of the user who starts the remote debugger
server.

It should be noted that the debugger server does not run as a service.
It must
be manually executed. Additionally, the remote debugger server can only
handle
one debugger session at a time. As such, this vulnerability can not be
exploited while the debugger server is in use.

IV. DETECTION

iDefense has confirmed the existence of this vulnerability in the remote
debugger server for Windows and Linux from IDA Pro versions 5.0 and 5.1. It
is suspected that the MacOS X version and earlier versions are also
affected.

V. WORKAROUND

In order to reduce exposure to this vulnerability, the remote debugger
server
should not be left running when it is not in use.

Additionally, access to the port used by the remote debugger server could be
blocked with the use of a firewall.

VI. VENDOR RESPONSE

"Since this vulnerability is in the open part of IDA, we provide the
corrected
source code for the modified files."

DataRescue Inc. has made the fix available at the following URL.

http://www.datarescue.com/freefiles/ida_remdeb_fix_22032007.zip

VII. CVE INFORMATION

A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not
been assigned yet.

VIII. DISCLOSURE TIMELINE

03/20/2007 Initial vendor notification
03/20/2007 Initial vendor response
03/23/2007 Coordinated public disclosure

IX. CREDIT

This vulnerability was reported to iDefense by enhalos.

Get paid for vulnerability research
http://labs.idefense.com/methodology/vulnerability/vcp.php

Free tools, research and upcoming events
http://labs.idefense.com/

X. LEGAL NOTICES

Copyright © 2007 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 e-mail
[email protected] 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.