crypto-js PBKDF2 1,000 times weaker than specified in 1993 and 1.3M times weaker than current standard
Date: 2023-10
Affected: npm/crypto-js
Attack vector: other
Category: vulnerability-disclosure
Severity: Critical
CVE: CVE-2023-46233
CWE: CWE-327
CWE-328
CWE-916
CVSS: 9.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N)

### Impact #### Summary Crypto-js PBKDF2 is 1,000 times weaker than originally specified in 1993, and [at least 1,300,000 times weaker than current industry standard][OWASP PBKDF2 Cheatsheet]. This is because it both (1) defaults to [SHA1][SHA1 wiki], a cryptographic hash algorithm considered insecure [since at least 2005][Cryptanalysis of SHA-1] and (2) defaults to [one single iteration][one iteration src], a 'strength' or 'difficulty' value specified at 1,000 when specified in 1993. PBKDF2 relies on iteration count as a countermeasure to [preimage][preimage attack] and [collision][collision attack] attacks. Potential Impact: 1. If used to protect passwords, the impact is high. 2. If used to generate signatures, the impact is high. Probability / risk analysis / attack enumeration: 1. [For at most $45,000][SHA1 is a Shambles], an attacker, given control of only the beginning of a crypto-js PBKDF2 input, can create a value which has _identical cryptographic signature_ to any chosen known value. 4. Due to the [length extension attack] on SHA1, we can create a value that has identical signature to any _unknown_ value, provided it is prefixed by a known value. It does not matter if PBKDF2 applies '[salt][cryptographic salt]' or '[pepper][cryptographic pepper]' or any other secret unknown to the attacker. It will still create an identical signature. Update: PBKDF2 requires a pseudo-random function that takes two inputs, so HMAC-SHA1 is used rather than plain SHA1. HMAC is not


Mitigations:

Architectural layers (MAESTRO):