MISP Missing Authorization in Cryptographic Key View Exposes Signing Keys from Protected Events

Affected versions of MISP do not enforce parent-event visibility when serving cryptographic keys through CryptographicKeysController::view().

The vulnerable handler queried CryptographicKey directly using the supplied key ID and selected sensitive fields such as:

*
type

*
key_data

*
fingerprint

but did not fetch or authorize the associated parent event first.

The upstream commit explicitly states that cryptographicKeys/view could return a protected event’s signing key to any authenticated user.

The fix adds parent_id and parent_type to the lookup and then enforces authorization through the associated event using fetchSimpleEvent($user, parent_id). If the parent is not an Event, access is limited to site administrators.

Version affected: ≤2.5.45