CVE-2023-6927

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.

What this means for your business

It affects Redhat Keycloak. It matters if your company, or a supplier that handles your data, runs it.
An attacker can use it remotely, over a network, with an ordinary user login, but only after tricking someone into an action such as opening a file or a link.
FIRST's prediction model gives it a 1% chance of attack attempts being seen in the next 30 days, ranking above 64% of all known flaws.

What to do

1Check whether your company or your suppliers run Redhat Keycloak, and which version. The affected versions are listed further down this page.
2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

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Scoring

CVSS: 4.6 (v3.1)
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
Weakness: CWE-601
Assigned by: secalert@redhat.com

Dates

Published: 2023-12-18
Last modified: 2026-09-22
Sources: NVD

Affected products

Redhat Keycloakall versions
Redhat Single Sign-On7.0

As listed in the NVD configuration data. Not a statement about your estate.