Source Code Disclosure - CVE-2012-1823

Remediation

To remediate this vulnerability, it is recommended to take the following actions:

1. Upgrade PHP version: Ensure that you are using the latest stable version of PHP, as newer versions often include security patches and bug fixes. This vulnerability was specifically addressed in PHP versions 5.3.12 and 5.4.2.

2. Switch to FastCGI or PHP-FPM: Instead of using CGI, consider using FastCGI or PHP-FPM (FastCGI Process Manager) to run PHP. These alternatives provide better performance and security features.

3. Implement input validation: Validate and sanitize all user input to prevent malicious query strings from being executed as code. Use appropriate input validation techniques such as whitelisting, blacklisting, and regular expressions to ensure that only expected and safe input is processed.

4. Disable display_errors: In your PHP configuration, ensure that the display_errors directive is set to Off. This prevents PHP error messages, including source code, from being displayed to the user in case of an error.

5. Secure sensitive files: Ensure that sensitive PHP files, such as configuration files or files containing sensitive code, are not accessible directly from the web browser. Store them outside the web root directory or use appropriate access controls to restrict access.

About

The vulnerability known as “Source Code Disclosure - CVE-2012-1823” affects certain versions of PHP when configured to run using CGI. It occurs when a query string lacks an unescaped “=” character, which can lead to the disclosure of PHP source code and potentially allow arbitrary code execution. In this scenario, the contents of the PHP file are served directly to the web browser, exposing PHP code and potentially HTML content.

Risks

The risks associated with this vulnerability include:

1. Source code exposure: The vulnerability allows an attacker to view the source code of PHP files, which may contain sensitive information such as database credentials, API keys, or proprietary algorithms. This information can be exploited to further compromise the system or launch targeted attacks.

2. Arbitrary code execution: If an attacker can execute arbitrary code, they can potentially take control of the affected system, escalate privileges, or perform unauthorized actions. This can lead to data breaches, unauthorized access, or disruption of services.

3. Information disclosure: The output served to the web browser may contain not only PHP code but also HTML content. This can expose sensitive information to users, such as internal file paths, error messages, or other system details that could aid attackers in further exploiting the system.

It is crucial to address this vulnerability promptly to prevent unauthorized access, protect sensitive information, and maintain the integrity and availability of the affected system.