Argon2d Hash

What is Argon2d?

Argon2d is a memory-hard key derivation function (KDF) designed as part of the Password Hashing Competition (PHC) sponsored by the Computer Emergency Response Team (CERT) in 2015, winning the competition in July 2015. Structurally, it is a variant of the Argon2 algorithm family, which itself builds upon the principles of memory-bound cryptographic primitives to resist hardware acceleration attacks. Argon2d is specifically optimized for *d*ata-dependent addressing, meaning its memory access patterns are influenced by the input data, enhancing resistance to side-channel attacks and parallelization. The algorithm operates by partitioning memory into blocks, filling them with data, and then mixing these blocks through a series of permutations and XOR operations, with parameters such as *m* (memory cost), *t* (time cost), and *p* (parallelism) controlling its computational and memory intensity. Its primary use-case is password hashing in authentication systems, where it provides a robust defense against brute-force and GPU/ASIC-based attacks by forcing attackers to allocate significant memory resources, thus mitigating the efficiency gains of specialized hardware.

Despite its strengths, Argon2d remains vulnerable to cracking due to its susceptibility to *optimized parallelization* and *side-channel timing attacks*. While its memory hardness mitigates GPU/ASIC acceleration, attackers can still exploit optimized CPU implementations (e.g., via AVX-512 or multi-threaded attacks) to reduce effective time complexity. Additionally, Argon2d’s reliance on a fixed memory layout can lead to *timing inconsistencies* if not properly implemented, allowing adversaries to infer information about the input data through side-channel analysis. Though collisions are theoretically unlikely due to its cryptographic design, practical attacks may exploit weaknesses in parameter selection (e.g., insufficient *m* or *t* values) to reduce the effective security margin. Finally, if salts are reused or omitted, Argon2d’s resistance degrades, as identical passwords would produce identical memory access patterns, enabling precomputed or rainbow table attacks.

Identifying Argon2d 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 Argon2d, security researchers analyze the hash against a strict regular expression (regex) signature (shown above) to find structural matches.

How to Crack Argon2d

If you need to recover the plaintext password for a Argon2d 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.