In ORY Fosite (the security first OAuth2 & OpenID Connect framework for Go) before version 0.31.0, when using "private_key_jwt" authentication the uniqueness of the `jti` value is not checked. When using client authentication method "private_key_jwt", OpenId specification says the following about assertion `jti`: "A unique identifier for the token, which can be used to prevent reuse of the token. These tokens MUST only be used once, unless conditions for reuse were negotiated between the parties". Hydra does not seem to check the uniqueness of this `jti` value. This problem is fixed in version 0.31.0.
Cite this page
CVE-2020-15222. CVEDatabase.com. Retrieved 1 May 2026. https://cvedatabase.com/cve/CVE-2020-15222
Use CWE-287, Ory vendor hub and Fosite product page to widen CVE-2020-15222 into its surrounding weakness, vendor, and product context.
Compare it with CVE-2020-15223, CVE-2020-15234 and CVE-2020-15233 for nearby disclosures in the same product family.