AlexanderLivanov FotosCMS2 Cookie profile.php cross site scripting

Successful exploitation of CVE-2023-5837 allows an attacker to inject arbitrary JavaScript code into the FotosCMS2 application. This can lead to session hijacking, phishing attacks, defacement of the website, or the theft of sensitive user data, such as login credentials and personal information. The attacker can potentially execute malicious code in the context of a user's browser, gaining unauthorized access to their account and performing actions on their behalf. Given the nature of XSS, the blast radius extends to all users who interact with the affected page, particularly those who log in or submit data.

Organizations and individuals using FotosCMS2 versions 2.4.0 through 2.4.3 are at risk. This includes websites and applications built on FotosCMS2, particularly those handling sensitive user data or requiring authentication. Shared hosting environments utilizing FotosCMS2 are also at increased risk due to the potential for cross-tenant exploitation.

• php: Examine profile.php for unsanitized use of the username parameter in output. Search for instances where user input is directly echoed to the page without proper encoding.

// Example of vulnerable code (simplified)
<?php
echo $_GET['username']; // Vulnerable to XSS
?>

• generic web: Monitor access logs for unusual requests to profile.php with suspicious parameters in the URL. Look for patterns indicative of XSS payloads.

grep -i 'script|alert|onerror' /var/log/apache2/access.log

1. 2023-10-28Disclosure

   disclosure

2. 2023-10-28Patch

   patch

1. Reservado2023-10-28
2. Publicada2023-10-28
3. Modificada2024-08-27
4. EPSS atualizado2026-04-02

The primary mitigation for CVE-2023-5837 is to upgrade FotosCMS2 to version 2.4.4 or later, which contains the necessary fix. If upgrading immediately is not feasible, consider implementing input validation and output encoding on the username parameter in profile.php to sanitize user-supplied data. Web application firewalls (WAFs) can be configured to detect and block XSS attempts targeting this specific vulnerability. Regularly review and update your security policies and procedures to prevent similar vulnerabilities from arising.