Symfony's OidcTokenHandler Accepts JWTs Missing aud/iss/exp Claims
Date: 2026-05
Affected: composer/symfony/symfony, composer/symfony/symfony, composer/symfony/symfony
Attack vector: other
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2026-45069
CWE: CWE-1287
CWE-345

### Description `OidcTokenHandler` is Symfony's built-in access-token handler for OpenID Connect: it validates a bearer JWT and returns the authenticated user identity. It delegates claim validation to the `web-token/jwt-checker` library's `ClaimCheckerManager`. `OidcTokenHandler::verifyClaims()` registers audience (`aud`), issuer (`iss`), and expiry (`exp`) checkers, but never passes the `$mandatoryClaims` argument to `ClaimCheckerManager::check()`. That method only validates claims that are *present* in the token: a checker for an absent claim is silently skipped. A validly-signed JWT that simply **omits** `aud`, `iss`, and `exp` therefore passes verification. ### Resolution The `OidcTokenHandler` now calls the `ClaimCheckerManager` with the list of mandatory claims so that tokens missing `aud`, `iss`, or `exp` are rejected. The patch for this issue is available [here](https://github.com/symfony/symfony/commit/6b717aaac21b7e96798448d14c4355ea87690b3d) for branch 6.4. ### Credits Symfony would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.


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Architectural layers (MAESTRO):