MySQL MaxDB Webtool Remote 'If' Stack Overflow Vulnerability

iDEFENSE Security Advisory 04.26.05
www.idefense.com/application/poi/display?id=236&type=vulnerabilities
April 26, 2005

I. BACKGROUND

MaxDB by MySQL is a re-branded and enhanced version of SAP DB, SAP AG's
open source database. MaxDB is a heavy-duty, SAP-certified open source
database that offers high availability, salability and a comprehensive
feature set. MaxDB complements the MySQL database server, targeted for
large mySAP ERP environments and other applications that require maximum
enterprise-level database functionality.

II. DESCRIPTION

Remote exploitation of a stack-based buffer overflow vulnerability in 
MySQL MaxDB could allow attackers to execute arbitrary code. 

The vulnerabiltiy specifically exists because of a lack of bounds 
checking in the WebDAV functionality of the web tool. When an attacker 
issues an HTTP request with the unlock method, along with a long "If" 
parameter string, a stack-based overflow occurs. The offending code 
follows: 

WDVH_Bool getIfHeader(sapdbwa_HttpRequestP request,
                      WDVH_Char *sIf,
                      WDVH_Int4 len)
{
WDVH_Char       *temp1, *temp2, *temp4, *temp5;
WDVH_UInt4      length;
WDVH_Char       temp3[WDVH_MAX_IF_HEADER_LEN];

if (request==NULL || sIf==NULL)
    return WDVH_False;
  
strcpy(sIf,"");
temp4 = (char*)sapdbwa_GetHeader(request,"If");
if (temp4 != NULL) {
    strcpy(temp3,temp4); 

The variable temp3 is a fixed-length stack buffer. The function 
sapdbwa_GetHeader() returns the user-supplied value for the "If" 
parameter. This user-supplied value is then copied into the fixed-size 
buffer using a strcpy() call. Because there is no boundary checking, it 
is possible to overflow the stack buffer and overwrite stack memory, 
ultimately leading to control of execution flow and execution of 
arbitrary code.

III. ANALYSIS

Successful exploitation of the vulnerability could allow remote 
attackers to execute code with SYSTEM privileges. Note that the 
vulnerability is in the web administration service, which should be 
configured to not allow connections from untrusted hosts or listening on

public-facing network interfaces.

IV. DETECTION

iDEFENSE has confirmed the existence of this vulnerability in MySQL 
MaxDB 7.5.00.23. All versions are suspected vulnerable.

V. WORKAROUND

Filter traffic on TCP port 9999 from untrusted hosts destined for the 
MaxDB Webtool server.

VI. VENDOR RESPONSE

This vulnerability is fixed in MySQL MaxDB 7.5.00.26 which available for
download at:

   http://dev.mysql.com/downloads/maxdb/7.5.00.html

VII. CVE INFORMATION

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

VIII. DISCLOSURE TIMELINE

04/25/2005  Initial vendor notification
04/26/2005  Initial vendor response
04/26/2005  Coordinated public disclosure

IX. CREDIT

iDEFENSE Labs is credited with this discovery.

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X. LEGAL NOTICES

Copyright (c) 2005 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
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There are no warranties with regard to this information. Neither the
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