CVE-2016-10082

Step 1: Installation Initiation: The attacker initiates the Serendipity installation process, typically by accessing the setup URL. Step 2: Parameter Manipulation: The attacker crafts a malicious dbType POST parameter. This parameter is designed to point to a malicious PHP file, either hosted locally on the server (if file access is possible) or remotely on a server controlled by the attacker. Step 3: Payload Delivery (if remote): If the attacker is using a remote file, the malicious PHP code is hosted on a server they control. This code will contain commands to be executed on the target server. Step 4: Vulnerable Include: The serendipity_generateFTPChecksums.php file includes the attacker-controlled file using the attacker-supplied dbType value. Step 5: Code Execution: The malicious PHP code within the included file is executed by the web server, granting the attacker control over the server. This could include actions like creating backdoors, stealing data, or further compromising the system.

The vulnerability lies within the include/functions_installer.inc.php file and the bundled-libs/serendipity_generateFTPChecksums.php file of Serendipity versions up to 2.0.5. The dbType POST parameter, used during the initial installation, is directly incorporated into an include() call within serendipity_generateFTPChecksums.php without proper sanitization or validation. This allows an attacker to control which file is included. By crafting a malicious dbType value, an attacker can include a local or remote file containing PHP code. This code is then executed by the web server, leading to remote code execution. The root cause is a lack of input validation and improper use of the include() function with user-controlled input.