GHSA-v3q9-2p3m-7g43

    Dashboard / Vulnerabilities / GHSA-v3q9-2p3m-7g43

    GHSA-v3q9-2p3m-7g43

    Published: 24 May 2021Last Modified: 8 Jul 2026

    Summary: Token reuse in Ory fosite

    Details: ### Impact When using client authentication method "private_key_jwt" [[1]](https://openid.net/specs/openid-connect-core-1_0.html#ClientAuthentication), 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. Here is me sending the same token request twice, hence with the same `jti` assertion, and getting two access tokens: ``` $ curl --insecure --location --request POST 'https://localhost/_/oauth2/token' \ --header 'Content-Type: application/x-www-form-urlencoded' \ --data-urlencode 'grant_type=client_credentials' \ --data-urlencode 'client_id=c001d00d-5ecc-beef-ca4e-b00b1e54a111' \ --data-urlencode 'scope=application openid' \ --data-urlencode 'client_assertion_type=urn:ietf:params:oauth:client-assertion-type:jwt-bearer' \ --data-urlencode 'client_assertion=eyJhb [...] jTw' {"access_token":"zeG0NoqOtlACl8q5J6A-TIsNegQRRUzqLZaYrQtoBZQ.VR6iUcJQYp3u_j7pwvL7YtPqGhtyQe5OhnBE2KCp5pM","expires_in":3599,"scope":"application openid","token_type":"bearer"}⏎ $ curl --insecure --location --request POST 'https://localhost/_/oauth2/token' \ --header 'Content-Type: application/x-www-form-urlencoded' \ --data-urlencode 'grant_type=client_credentials' \ --data-urlencode 'client_id=c001d00d-5ecc-beef-ca4e-b00b1e54a111' \ --data-urlencode 'scope=application openid' \ --data-urlencode 'client_assertion_type=urn:ietf:params:oauth:client-assertion-type:jwt-bearer' \ --data-urlencode 'client_assertion=eyJhb [...] jTw' {"access_token":"wOYtgCLxLXlELORrwZlmeiqqMQ4kRzV-STU2_Sollas.mwlQGCZWXN7G2IoegUe1P0Vw5iGoKrkOzOaplhMSjm4","expires_in":3599,"scope":"application openid","token_type":"bearer"} ``` ### Patches This issue is patched in 0.31.0. ### Workarounds Do not allow clients to use `private_key_jwt`. ### References https://openid.net/specs/openid-connect-core-1_0.html#ClientAuthentication

    Affected packages

    Package

    Name: github.com/ory/fosite

    Purl: pkg:golang/github.com/ory/fosite

    Affected ranges

    Type: SEMVER

    Events:

    Introduced- 0
    Fixed -0.31.0

    Affected versions

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    GHSA-v3q9-2p3m-7g43 | CVE-DB