Woltlab Burning Board 4.x Hash

What is Woltlab Burning Board 4.x?

The Woltlab Burning Board 4.x password hashing scheme is a custom cryptographic format introduced in the mid-2000s as part of the Woltlab Burning Board (WBB) forum software suite, a PHP-based discussion platform. This algorithm was designed as a lightweight alternative to established hashing standards like MD5 or SHA-1, incorporating a two-step process to mitigate trivial rainbow table attacks. Structurally, it begins with a SHA-1 hash of the plaintext password, followed by a variable-length salt derived from the user’s email address (if provided) or a system-generated value. The resulting hash is then iteratively processed through a custom "burning" function—essentially a series of bitwise XOR operations combined with modular arithmetic—before being stored in a 40-character hexadecimal string. This format was primarily intended for backward compatibility and performance optimization in resource-constrained environments, prioritizing speed over security. However, its lack of formal cryptographic scrutiny led to widespread adoption despite critical flaws.

The Woltlab Burning Board 4.x hashing scheme is fundamentally vulnerable due to its reliance on predictable salts, weak iteration mechanisms, and susceptibility to GPU-accelerated cracking. The salt derivation from user emails (or fixed system values) creates a collision risk where multiple users share identical salts, reducing the hash space diversity. The "burning" process—comprising a fixed number of XOR operations (typically 1024) with no adaptive work factor—is easily parallelizable on modern GPUs, enabling brute-force attacks via tools like Hashcat with optimized kernels. Additionally, the absence of a salted final hash (e.g., pepper or per-user salts) allows attackers to precompute hashes for common passwords, rendering the scheme susceptible to rainbow table attacks. The lack of key stretching (e.g., PBKDF2 or bcrypt) further exacerbates this, as the computational overhead is minimal, allowing for rapid enumeration of password candidates. These architectural deficiencies render WBB 4.x hashes trivial to crack in contemporary threat models.

Identifying Woltlab Burning Board 4.x Hashes

Identifying a hash blindly is often difficult because multiple algorithms can output strings of the exact same length. For example, a standard 32-character hexadecimal string could be MD5, NTLM, MD4, or LM. To definitively identify Woltlab Burning Board 4.x, security researchers analyze the hash against a strict regular expression (regex) signature (shown above) to find structural matches.

How to Crack Woltlab Burning Board 4.x

If you need to recover the plaintext password for a Woltlab Burning Board 4.x hash during a penetration test or forensics investigation, you must supply the correct module ID to your cracking software. Use the exact commands provided at the top of this page to target the hash successfully.