Description
AmoyLab Unla through 0.10.0 contains an authentication bypass vulnerability that allows unauthenticated attackers to obtain valid access tokens because the OAuth2 server never authenticates a resource owner. Attackers can register a client, request a code from /authorize, and exchange it at /token to access OAuth2-protected MCP prefixes, proxied upstream APIs and injected credentials.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| AmoyLab | Unla | ≤ 0.10.0 | — |
References
- https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/amoylab-unla-oauth-self-issued-token-authz third-party-advisory
- https://github.com/AmoyLab/Unla/blob/v0.10.0/internal/auth/oauth.go#L86-L147 technical-description
- https://github.com/AmoyLab/Unla/blob/v0.10.0/internal/core/server.go#L229-L261 technical-description
- https://github.com/AmoyLab/Unla product
- VulnCheck Advisory: AmoyLab Unla through 0.10.0 OAuth2 Authentication Bypass via /authorize third-party-advisory