Is CVE-2026-107623 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-107623 being exploited in the wild.

How severe is CVE-2026-107623?

Medium severity, with a CVSS score of 4.3, published 8 October 2026.

Which products and versions are affected?

Red Hat build of Keycloak before 26.6.8.

Is there a fix for CVE-2026-107623?

Yes: fixed in Red Hat build of Keycloak 26.6.8. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-107623 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-107623?

Check whether you run Red Hat build of Keycloak 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-2026-107623: Keycloak OIDC Dynamic Client Registration offline token revocation bypass

CVE-2026-107623 · Severity: medium · CVSS 4.3 · Published 2026-10-08

Keycloak is an open-source identity and access management system that handles single sign-on for web and mobile applications. A bug in the OIDC Dynamic Client Registration component causes the backchannel logout offline token revocation setting to be silently disabled during client updates, allowing offline tokens to remain valid after a user's session is terminated. This could allow a user with a revoked offline token to continue accessing protected resources.

Technologies: Red Hat build of Keycloak. Vendors: Red Hat.

Quick answers

Is CVE-2026-107623 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-107623 being exploited in the wild.
How severe is CVE-2026-107623?: Medium severity, with a CVSS score of 4.3, published 8 October 2026.
Which products and versions are affected?: Red Hat build of Keycloak before 26.6.8.
Is there a fix for CVE-2026-107623?: Yes: fixed in Red Hat build of Keycloak 26.6.8. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-107623 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-107623?: Check whether you run Red Hat build of Keycloak 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

Fixed in: Red Hat build of Keycloak 26.6.8

Technical details

The OIDC Dynamic Client Registration (DCR) endpoint has a response serialization bug that omits the backchannel logout offline token revocation setting when returning client configuration. When a client performs a standard update operation, this missing information causes the setting to be silently disabled, leaving offline tokens valid even after backchannel logout. No authentication is required to register a dynamic client; the vulnerability requires client-side action to trigger the configuration update.

Affected products

Red Hat build of Keycloak before 26.6.8

Timeline

2026-10-08: disclosed
2026-11-06: advisory

References

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