To understand b374k.php, one must understand the hierarchy of web shells. There are dozens of families: c99 (the granddaddy), r57, WSO (Web Shell by oRb), b374k, and more modern ones like p0wny-shell.

| Feature | c99/madShell | WSO | b374k | | :--- | :--- | :--- | :--- | | GUI Complexity | High (HTML heavy) | Medium | Medium/High | | File Manager | Yes | Yes | Yes (with AJAX) | | SQL Management | Basic | Good | Excellent | | Reverse Shell | Manual | Yes | Automated generator | | Stealth | Poor (large size) | Medium | Good (obfuscation built in) | | Password grabbing | Yes | Yes | Auto-scan for creds |

Why b374k stands out: Unlike older shells that look like 1990s hacker forums, b374k offers a relatively clean, responsive interface with a file tree explorer similar to an FTP client. This usability makes it a favorite among less-skilled attackers (script kiddies) and professional red teams alike.

The majority of b374k uploads exploit known vulnerabilities from 2018-2022 that remain unpatched. Autoupdate WordPress, Drupal, Joomla, and all plugins.

Once a quarter, hire an ethical hacker to attempt placing a b374k.php on your staging server. Use their findings to close gaps.

| Attribute | Details | | :--- | :--- | | Filename | b374k.php (can be renamed to any .php, .php5, .phtml, etc.) | | Typical Size | 10KB – 200KB (depending on version and obfuscation) | | File Hash (Example) | 7a3e7f9b8c2d1a5e6f4g8h2i3j4k5l6m (varies by version) | | First Seen | ~2012 (still actively used in 2025) |

Modern cloud deployments (Docker, Kubernetes) can mount the PHP application code as read-only. Even if an attacker uploads b374k.php, they cannot write it to disk.

b374k allows file uploads. Monitor your /tmp directory. If you see PHP scripts writing to /tmp/sess_* or executing system() functions where they shouldn't, investigate.

Tools like Tripwire or AIDE hash every PHP file daily. When a new file appears in /var/www/html, the admin is alerted. b374k.php cannot hide from FIM.