MISP: Improper UUID validation in MISP Collections

MISP is an open source threat intelligence and sharing platform. Prior to 2.5.37, MISP Collections did not enforce RFC 4122 UUID validation on the uuid field. As a result, a user able to create or modify Collection records could submit malformed UUID values, potentially causing integrity issues or unexpected behaviour in code paths that assume Collection UUIDs are valid identifiers. This vulnerability is fixed in 2.5.37.