The vulnerability arises from the MISP Collection interface not enforcing RFC 4122 UUID validation on the uuid field before version 2.5.37. Because the platform accepts malformed UUIDs, a user who can create or modify Collection records could submit values that break assumptions or data integrity checks in downstream code. This weakness could lead to corrupted data, unexpected behavior, or inconsistencies in collection handling. The weakness is classified as CWE‑20 (Improper Input Validation).

The affected product is MISP, the open‑source threat‑intelligence platform, specifically versions prior to 2.5.37. The vulnerability is present in all installations of MISP that allow users to create or edit Collection objects without fixing the UUID format.

With a CVSS score of 5.3, the vulnerability is considered moderate. The EPSS score is <1% (0.00084), indicating a low probability of exploitation, and the vulnerability is not listed in the CISA KEV catalog. The likely attack vector is via authenticated user access to the MISP API or web interface, where a privileged user can submit a malformed UUID. Since the flaw impacts integrity rather than confidentiality or availability, the immediate risk is to data consistency and potential application errors.