is PBKDF2 reversible? Given an AES key that is wrapped using another AES key, the second one being generated using PBKDF2, and given that I know the wrapped key: can I derive the passphrase that went into the PBKDF2? (asking for a friend)
PBKDF2 is not reversible using any semi-safe underlying hash function, including for instance SHA1 or even MD5.