Authorization Bypass Through User-Controlled Key Affecting authlib package, versions [0.15,1.9.1)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published27 Oct 2026
- disclosed27 Oct 2026
- creditAlham Rizvi
Introduced: 27 Oct 2026
NewCVE-2026-116672 (opens in a new tab)How to fix?
Upgrade authlib to version 1.9.1 or higher.
Overview
authlib is a library in building OAuth and OpenID Connect servers.
Affected versions of this package are vulnerable to Authorization Bypass Through User-Controlled Key via the create_configuration_response method in authlib/oauth2/rfc7592/endpoint.py, where a registration access token issued to one client is accepted as valid for any other client's configuration endpoint. An authenticated attacker can present a valid registration access token obtained for their own client and use it to read, modify, or delete the configuration of a different client on the same server.