CVE-2023-6927: Keycloak: open redirect via "form_post.jwt" jarm response mode

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-12-18 · updated 2026-09-22
Weakness: CWE-601

Description

A flaw was found in Keycloak. This issue may allow an attacker to steal authorization codes or tokens from clients using a wildcard in the JARM response mode "form_post.jwt" which could be used to bypass the security patch implemented to address CVE-2023-6134.

Affected products

Keycloak: all versions
Red Hat Single Sign-On: 7.0

References

https://access.redhat.com/errata/RHSA-2024:0094
https://access.redhat.com/errata/RHSA-2024:0095
https://access.redhat.com/errata/RHSA-2024:0096
https://access.redhat.com/errata/RHSA-2024:0097
https://access.redhat.com/errata/RHSA-2024:0098
https://access.redhat.com/errata/RHSA-2024:0100
https://access.redhat.com/errata/RHSA-2024:0101
https://access.redhat.com/errata/RHSA-2024:0798
https://access.redhat.com/errata/RHSA-2024:0799
https://access.redhat.com/errata/RHSA-2024:0800
https://access.redhat.com/errata/RHSA-2024:0801
https://access.redhat.com/errata/RHSA-2024:0804

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