sha1(unicode($pass).$salt) Hash

What is sha1(unicode($pass).$salt)?

SHA-1 (Secure Hash Algorithm 1) was introduced in 1995 by the NSA as part of the Digital Signature Standard (FIPS-180) to provide a 160-bit (20-byte) cryptographic hash function for data integrity verification, digital signatures, and password storage. The format `sha1(unicode($pass).$salt)` combines SHA-1 with a per-user salt by concatenating the Unicode-encoded password string with a unique salt value before hashing. This construction was designed to mitigate basic rainbow table attacks by ensuring each password hash is unique to its salt, though the salt itself is typically stored alongside the hash. The primary use-case for this format was password hashing in systems where memory efficiency and moderate security were prioritized over modern cryptographic standards, such as in legacy authentication schemes or systems with constrained resources.

The vulnerability of `sha1(unicode($pass).$salt)` stems from SHA-1’s inherent weaknesses, including its susceptibility to collision attacks (e.g., SHA-1 is now considered broken for security purposes due to practical collision exploits) and its slow processing speed relative to modern hardware. Even with a salt, brute-force attacks remain feasible due to SHA-1’s relatively fast computation—especially when optimized on GPUs or FPGA-based hardware (e.g., via tools like Hashcat or custom ASICs). The Unicode normalization step introduces potential side-channel vulnerabilities if not handled securely, and the 160-bit output space is now considered insufficient for password hashing given today’s computational power. Additionally, the lack of key stretching (unlike PBKDF2 or bcrypt) means attackers can evaluate millions of hashes per second, rendering it vulnerable to dictionary and hybrid attacks.

Identifying sha1(unicode($pass).$salt) 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 sha1(unicode($pass).$salt), security researchers analyze the hash against a strict regular expression (regex) signature (shown above) to find structural matches.

How to Crack sha1(unicode($pass).$salt)

If you need to recover the plaintext password for a sha1(unicode($pass).$salt) 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.