IPMI2 RAKP HMAC-SHA1 Hash

What is IPMI2 RAKP HMAC-SHA1?

The **IPMI2 RAKP HMAC-SHA1** cryptographic format is derived from the **Intelligent Platform Management Interface (IPMI) version 2.0** protocol, standardized by the DMTF (now part of the Distributed Management Task Force) in 2007. It is a **Key Exchange and Authentication Protocol (RAKP)** mechanism designed to secure out-of-band (OOB) management access to server hardware via the IPMI interface, which operates independently of the primary OS. The format leverages **HMAC-SHA1** (Hash-based Message Authentication Code with SHA-1) as its cryptographic primitive, embedding it within a structured payload that includes **nonce (N), challenge (C), and key exchange parameters (K)**. The RAKP process authenticates both the client and server using pre-shared secrets (e.g., IPMI user credentials) and derives session keys via a **three-way handshake**, where each message is signed and hashed to prevent replay attacks. Its primary use-case is securing remote management access to enterprise-grade hardware (e.g., Dell iDRAC, HP iLO, Lenovo XClarity) by ensuring integrity and confidentiality of RAKP messages, though it does not encrypt payload data beyond the handshake phase.

The **vulnerability of IPMI2 RAKP HMAC-SHA1** stems from **fundamental cryptographic weaknesses inherent in SHA-1 and its implementation**. SHA-1 is now considered **collision-prone** due to its 160-bit output space, which has been exploited via **pre-image attacks** (e.g., SHA-1crack) and **length-extension attacks** when improperly concatenated. The absence of **salting** in HMAC-SHA1 allows attackers to precompute rainbow tables for weak passwords, enabling offline brute-force cracking of user credentials. Additionally, the **lack of forward secrecy**—due to static key derivation—exposes sessions to compromise if long-term secrets are leaked. GPU-accelerated tools like **Hashcat** can perform **massive parallel brute-force attacks** on HMAC-SHA1 due to its **linear complexity** (O(n)), and optimizations like **bitmasking** further reduce cracking time. Finally, the **fixed-length nonce (N) and predictable challenge (C) formats** in RAKP enable **dictionary attacks** when combined with leaked credentials, as the attack surface scales poorly with password complexity.

Identifying IPMI2 RAKP HMAC-SHA1 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 IPMI2 RAKP HMAC-SHA1, security researchers analyze the hash against a strict regular expression (regex) signature (shown above) to find structural matches.

How to Crack IPMI2 RAKP HMAC-SHA1

If you need to recover the plaintext password for a IPMI2 RAKP HMAC-SHA1 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.