Is CVE-2026-116672 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-116672 being exploited in the wild.

How severe is CVE-2026-116672?

High severity, with a CVSS score of 8.8, published 27 October 2026.

Which products and versions are affected?

Authlib 0.15 to 1.9.0; authlib (PyPI) ECOSYSTEM:introduced=0.15,fixed=1.9.1; Authlib >= 0.15, <= 1.9.0.

Is there a fix for CVE-2026-116672?

Yes. authlib (PyPI): upgrade to 1.9.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-116672 attacked?

It is attacked over the network.

Am I affected by CVE-2026-116672?

Check whether you run Authlib, authlib (PyPI) or Authlib at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-116672: Authlib client configuration endpoint authorization bypass

Q: Is there a fix for CVE-2026-116672?

Yes. authlib (PyPI): upgrade to 1.9.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-116672 attacked?

It is attacked over the network.

Q: Am I affected by CVE-2026-116672?

Check whether you run Authlib, authlib (PyPI) or Authlib at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-116672 · Severity: high · CVSS 8.8 · Published 2026-10-27

Authlib is a Python library for building OAuth and OpenID Connect servers. The ClientConfigurationEndpoint reference implementation incorrectly validates client ownership, allowing an attacker with any valid registration access token to read, modify, or delete another client's registration. This enables attackers to intercept authorization codes and tokens or deny service to legitimate clients.

Technologies: Authlib, authlib (PyPI). Vendors: Authlib, PyPI.

Quick answers

Is CVE-2026-116672 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-116672 being exploited in the wild.
How severe is CVE-2026-116672?: High severity, with a CVSS score of 8.8, published 27 October 2026.
Which products and versions are affected?: Authlib 0.15 to 1.9.0; authlib (PyPI) ECOSYSTEM:introduced=0.15,fixed=1.9.1; Authlib >= 0.15, <= 1.9.0.
Is there a fix for CVE-2026-116672?: Yes. authlib (PyPI): upgrade to 1.9.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-116672 attacked?: It is attacked over the network.
Am I affected by CVE-2026-116672?: Check whether you run Authlib, authlib (PyPI) or Authlib at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

authlib (PyPI): upgrade to 1.9.1 or later
```
pip install "authlib>=1.9.1"
```

Technical details

The ClientConfigurationEndpoint.authenticate_client and check_permission reference implementations check whether a target client is editable but fail to verify that request.credential belongs to that client. An attacker can supply an arbitrary client_id in a request and use a valid registration access token from a different client to bypass authorization checks. Exploitation requires network access and a valid registration access token from any client.

Affected products

Authlib Authlib 0.15 to 1.9.0

Identifiers

CVE-2026-116672
GHSA-c73q-w75p-j82v

Timeline

2026-10-27: disclosed
2026-10-14: patched

References

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