VYPR
Moderate severityNVD Advisory· Published Dec 18, 2023· Updated Nov 11, 2025

Keycloak: open redirect via "form_post.jwt" jarm response mode

CVE-2023-6927

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.

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Keycloak's JARM form_post.jwt response mode open redirect allows token theft, bypassing CVE-2023-6134 patch.

Vulnerability

Overview CVE-2023-6927 is an open redirect vulnerability in Keycloak's JARM (JWT Authorization Response Mode) implementation, specifically in the form_post.jwt response mode. The flaw occurs when a wildcard is used in the redirect URI, allowing an attacker to redirect the user's browser to an arbitrary external site after authentication [1][2]. This effectively bypasses the security fix applied for CVE-2023-6134.

Exploitation

An attacker can craft a malicious link that leverages a client configured with a wildcard in the redirect URI pattern. When the victim authenticates, Keycloak sends the authorization code or token to the attacker-controlled redirect URI via a JWT in a form post. No authentication is required for the attacker, only the ability to trick a user into clicking the crafted link [1].

Impact

Successful exploitation allows the attacker to steal authorization codes or tokens, leading to account takeover or unauthorized access to protected resources [2].

Mitigation

Red Hat has released patches for Red Hat Single Sign-On 7.6.6 (RHSA-2024:0097) and Red Hat build of Keycloak 22.0.8 (RHSA-2024:0100) which address this vulnerability [3][4]. Users should upgrade to these versions or apply the provided mitigations.

AI Insight generated on May 20, 2026. Synthesized from this CVE's description and the cited reference URLs; citations are validated against the source bundle.

Affected packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
org.keycloak:keycloak-coreMaven
< 23.0.423.0.4

Affected products

23

Patches

0

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

17

News mentions

0

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