GHSA-9jxq-5x44-gx23

### Impact The Keylime `registrar` implemented more strict type checking on version 7.12.0. As a result, when updated to version 7.12.0, the `registrar` will not accept the format of the data previously stored in the database by versions >= 7.8.0, raising an exception.

This makes the Keylime `registrar` vulnerable to a Denial-of-Service attack in an update scenario, as an attacker could populate the `registrar` database by creating multiple valid agent registrations with different UUIDs while the version is still < 7.12.0. Then, when the Keylime `registrar` is updated to the 7.12.0 version, any query to the database matching any of the entries populated by the attacker will result in failure.

### Patches Users should upgrade to versions >= 7.12.1

### Workarounds - Remove the registrar database and re-register all agents

### Credit

Reported by: Anderson Toshiyuki Sasaki/@ansasaki Patched by: Anderson Toshiyuki Sasaki/@ansasaki