CVE-2026-32245
published 2026-03-12CVE-2026-32245: 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…
PriorityP343medium6.5CVSS 3.1
AVNACHPRNUINSUCLIHAN
EPSS
0.25%
16.3th percentile
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
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github.com | steveiliop56_tinyauth | >= 0 < 1.0.1-20260311144920-9eb2d33064b7 | 1.0.1-20260311144920-9eb2d33064b7 |
| steveiliop56 | tinyauth | < 5.0.3 | 5.0.3 |
| tinyauth | tinyauth | <= 5.0.2 | — |
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OSV
Tinyauth's OIDC authorization codes are not bound to client on token exchange in github.com/steveiliop56/tinyauth
osv·2026-03-12
CVE-2026-32245 Tinyauth's OIDC authorization codes are not bound to client on token exchange in github.com/steveiliop56/tinyauth
Tinyauth's OIDC authorization codes are not bound to client on token exchange in github.com/steveiliop56/tinyauth
Tinyauth's OIDC authorization codes are not bound to client on token exchange in github.com/steveiliop56/tinyauth.
NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions.
(If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.)
The additional affected modules and versions are: github.com/steveiliop56/tinyauth before v1.0.1-20260311144920-9eb2d33064b7.
OSV
Tinyauth's OIDC authorization codes are not bound to client on token exchange
osv·2026-03-12
CVE-2026-32245 [MEDIUM] Tinyauth's OIDC authorization codes are not bound to client on token exchange
Tinyauth's OIDC authorization codes are not bound to client on token exchange
### Summary
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.
### Details
When an authorization code is created, `StoreCode` at `internal/service/oidc_service.go:305-322` correctly stores the `ClientID` alongside the code hash in the database (line 316).
During token exchange at `internal/controller/oidc_controller.go:267-309`, the handler retrieves the code entry at line 268 and validates the `redirect_uri`
GHSA
Tinyauth's OIDC authorization codes are not bound to client on token exchange
ghsa·2026-03-12
CVE-2026-32245 [MEDIUM] CWE-863 Tinyauth's OIDC authorization codes are not bound to client on token exchange
Tinyauth's OIDC authorization codes are not bound to client on token exchange
### Summary
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.
### Details
When an authorization code is created, `StoreCode` at `internal/service/oidc_service.go:305-322` correctly stores the `ClientID` alongside the code hash in the database (line 316).
During token exchange at `internal/controller/oidc_controller.go:267-309`, the handler retrieves the code entry at line 268 and validates the `redirect_uri`
No detection rules found.
No public exploits indexed.
2026-03-12
Published