Vendor Phpunit Phpunit Src Util Php Eval-stdin.php Exploit ((free))

server listen 80; server_name example.com; root /var/www/my-app/public; # NOT /var/www/my-app index index.php; ... Use code with caution. 3. Block Access to vendor

Let’s look at the actual source code of eval-stdin.php (simplified for clarity):

The post-mortem revealed the real failure: a developer had run composer install --no-dev on the build server but used composer install (including dev dependencies) on the staging image. Then that image got promoted. Twice. vendor phpunit phpunit src util php eval-stdin.php exploit

Run this command in your web root directory to see if the vulnerable file exists:

Ensure your Apache DocumentRoot or Nginx root points to a public/ folder far away from vendor/ . server listen 80; server_name example

By placing malicious PHP payload code inside the body of the POST request, the attacker forces php://stdin to read that payload. The script then executes it with the privileges of the web server user (e.g., www-data ). This results in unauthenticated . How Attackers Exploit the Vulnerability

Because php://input reads raw data from the body of an HTTP request, a remote attacker can send a POST request containing malicious PHP code. Block Access to vendor Let’s look at the

: A 404 Not Found or 403 Forbidden status indicates the file is missing or correctly blocked. Remediation and Mitigation Steps

This article explores the technical mechanics of the exploit, why it lingers on production servers, how to weaponize it, and most importantly, how to eradicate it permanently.