CVE-2026-55584

Name of the Vulnerable Software and Affected Versions phpSysInfo versions prior to 3.4.6

Description An access-control bypass exists in the read config.php file when the PSI ALLOWED IP allowlist is configured. The application resolves the client IP address by trusting the X-Forwarded-For and Client-IP HTTP headers before considering the REMOTE ADDR variable. Because these headers are controlled by the user, a remote unauthenticated attacker can spoof a trusted IP address to bypass the restriction. This allows the attacker to access sensitive system information, including the hostname, kernel version, CPU details, memory layout, filesystem information, and network interface details.

Recommendations Update to version 3.4.6. As a temporary mitigation, restrict access to the read config.php file or the entire application at the web server level using a trusted IP filter that does not rely on HTTP headers.