privacyIDEA version 2.23.1 and earlier contains a Improper Input Validation vulnerability in token validation api that can result in Denial-of-Service. This attack appear to be exploitable via http request with user=&pass= to /validate/check url. This vulnerability appears to have been fixed in 2.23.2.
// cvss v3.0 vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Checked 2026-10-23 at 18:49 UTC. The most recent advisory here was published 2019-01-14. Updated continuously from NVD, GHSA, OSV and CNA feeds.