sandbox 2.0.3 – Multiple Vulnerabilities
Sandbox 2.0.3 Multiple Remote Vulnerabilities Name Sandbox Vendor http://www.iguanadons.net Versions Affected 2.0.3 Author Salvatore Fresta aka Drosophila Website http://www.salvatorefresta.net Contact salvatorefresta [at] gmail [dot] com Date 2010-07-07 X. INDEX I. ABOUT THE APPLICATION II. DESCRIPTION III. ANALYSIS IV. SAMPLE CODE V. FIX I. ABOUT THE APPLICATION ________________________ Sandbox is a personal website package that provides you with a blog, image gallery, file downloads area, and the ability to create miscellaneous custom webpages. II. DESCRIPTION _______________ Some parameters are not sanitised before being used in SQL queries and in danger PHP's functions. The vulnerabilities are reported in version 2.0.3. Other versions may also be affected. III. ANALYSIS _____________ Summary: A) Authentication Bypass B) Arbitrary File Upload C) Local File Inclusion D) SQL Injection A) Authentication Bypass ________________________ The sandbox_pass's cookie value in global.php is not properly sanitised before being used in a SQL query. Since this value is used for the authentication system, the injection can be used to bypass it. Successful exploitation requires that "magic_quotes_gpc" is disabled. B) Arbitrary File Upload ________________________ When a file is sent to blog.php (and also to profile.php) a bad check for extension is did. The check consists in dividing the file's name in substrings delimited by a point and checking if the second substring's value is present in the white list. This method works fine for a file with a single extension, but if an attacker uses a file with a double extension, this method doesn't work well. The following is the affected code in blog.php: $fname = $this->files['image_file']['tmp_name']; $system = explode( '.', $this->files['image_file']['name'] ); $system[1] = strtolower($system[1]); if ( !preg_match( '/jpg|jpeg|png|gif/', $system[1] ) ) { NO UPLOAD } else { UPLOAD } If the file's name is evil.jpg.php: $system[1] = jpg C) Local File Inclusion _______________________ The a parameter in admin.php is not properly sanitised before being used in the require() PHP's function. This can be exploited to include arbitrary files from local resources via directory traversal attacks and URL-encoded NULL bytes. D) SQL Injection ________________ The p parameter in modules/page.php is not properly sanitised before being used in a SQL query. This can be exploited to manipulate SQL queries by injecting arbitrary SQL code. IV. SAMPLE CODE _______________ A) Authentication Bypass cookie: sandbox_pass = 1' OR '1'='1'# cookie: sandbox_user = userid (1 for admin) B) Arbitrary File Upload Upload a file with a double extension. C) Local File Inclusion http://site/path/admin.php?a=../../../../../../../etc/passwd%00 D) SQL Injection http://site/path/index.php?a=page&p=-1 UNION SELECT 1,2,3,4,5,6,7,CONCAT(user_name,0x3a,user_password) FROM sb_users V. FIX ______ No fix. |