Vulnerability · Published Mar 12, 2026 · Assigned by GitHub_M
CVE-2026-32245Tinyauth's OIDC authorization codes are not bound to client on token exchange
Medium 6.5
In plain English
A medium-severity incorrect authorization in tinyauth from steveiliop56. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Tinyauth is an authentication and authorization server. Prior to 5.0.3, the OIDC token endpoint does not verify that the client exchanging an authorization code is the same client the code was issued to. A malicious OIDC client operator can exchange another client's authorization code using their own client credentials, obtaining tokens for users who never authorized their application. This violates RFC 6749 Section 4.1.3. This vulnerability is fixed in 5.0.3.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/steveiliop56/tinyauth | 1.0.1-20260311144920-9eb2d33064b7 | GHSA-xg2q-62g2-cvcm |
| Go | github.com/steveiliop56/tinyauth | no fix listed | GO-2026-4689 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| steveiliop56 | tinyauth | < 5.0.3 |
Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:H/A:N