vulnerability / NVI-00016002 / Revision 1
Gitea: OAuth token introspection returns metadata of tokens issued to other clients (RFC 7662 section 4 violation)
GitHub lists this reviewed advisory for code.gitea.io/gitea. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
4.3 medium
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
code.gitea.io/gitea
source listed< 1.27.0
## Live reproduction against Gitea 1.26.1 Setup: Gitea 1.26.1 docker stack with two users (`admin` and `victim`) and two OAuth applications owned by different users: ``` Client A: id=5dda747d-7fdd-4694-85ff-ce4f893ce51e owner=admin Client B: id=588f778f-4a41-4914-ae01-85d776c369db owner=victim ``` `admin` runs an OAuth flow against Client A and obtains an access token. `victim` (acting through Client B's credentials) calls the introspection endpoint with Client A's access token in the body: ``` $ curl -s -u "$B_ID:$B_SEC" -X POST http://localhost:3001/login/oauth/introspect \ --data-urlencode "token=$CLIENT_A_ACCESS_TOKEN" { "active": true, "username": "admin", "iss": "http://localhost:3001", "sub": "1", "aud": [ "5dda747d-7fdd-4694-85ff-ce4f893ce51e" ] } ``` Note the `aud` claim: the server explicitly states the token's audience is Client A, yet returns the full metadata to Client B. Per RFC 7662 section 4 ("The authorization server SHOULD also limit the information it discloses about each token to the resources that are authorized to receive it") the introspection result must not be disclosed to clients other than the token's audien
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-vxv2-8j6r-pcpg ↗
GitHub Advisory Database · vendor advisory
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Public revision history
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- Revision 1 ·
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