FrankenPHP is a modern application server for PHP. Prior to 1.12.5, the official FrankenPHP Debian and Alpine Docker images include a default /app/public/index.php that executes phpinfo(). A derived image that does not overwrite this placeholder serves the diagnostics page in production and can disclose environment variables used for secrets, PHP configuration directives, loaded extensions, software versions, and system paths.
Images built using the documented pattern with their own /app/public/index.php are not affected, and already derived images must be rebuilt or supplied with an application index to remove the exposed placeholder. This issue is fixed in version 1.12.5.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 4
https://github.com/php/frankenphp/commit/17940ff2ee188a1e48aabd10c095df72b42539…
security-advisories@github.com
https://github.com/php/frankenphp/pull/2524
security-advisories@github.com
https://github.com/php/frankenphp/releases/tag/caddy/v1.12.5
security-advisories@github.com
https://github.com/php/frankenphp/security/advisories/GHSA-cj57-c655-p798
security-advisories@github.com