Description
An unauthenticated attacker can send a crafted GET request directly to /oauth/:provider/callback with a forged profile in the query string. The OAuth service’s authentication payload has a fallback chain that reaches params.query (the raw request query) when Grant’s session/state responses are empty.
Recommendation
Update the @feathersjs/authentication-oauth package to the latest compatible version. Followings are version details:
- Affected version(s): >= 5.0.0, <= 5.0.41
- Patched version(s): 5.0.42
References
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- Feathers has an open redirect in OAuth callback enables account takeover - CVE-2026-27191
- Feathers has an origin validation bypass via prefix matching - CVE-2026-27192
- Feathers exposes internal headers via unencrypted session cookie - CVE-2026-27193
- SillyTavern has a Path Traversal issue - CVE-2026-44650


