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Fencer Vulns
medium 4.6

CVE-2023-6927 json

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

published 2023-12-18 2 y ago modified 2026-09-22 48 d ago also EUVD-2024-0318 , GHSA-9vm7-v8wj-3fqw

cvss
4.6
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.1%
EPSS 1.1% chance of exploitation in 30 days, percentile 66%
public exploits
0
none known

Summary

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.

Patch / fix

  • maven org.keycloak:keycloak-core 23.0.4
  • Red Hat Red Hat build of Keycloak 22 22-7
  • Red Hat Red Hat Single Sign-On 7.6 for RHEL 7 0:18.0.11-3.redhat_00001.1.el7sso, 0:18.0.12-1.redhat_00001.1.el7sso
  • Red Hat Red Hat Single Sign-On 7.6 for RHEL 8 0:18.0.11-3.redhat_00001.1.el8sso, 0:18.0.12-1.redhat_00001.1.el8sso
  • Red Hat Red Hat Single Sign-On 7.6 for RHEL 9 0:18.0.11-3.redhat_00001.1.el9sso, 0:18.0.12-1.redhat_00001.1.el9sso
  • Red Hat RHEL-8 based Middleware Containers 7.6-39, 7.6-41
  • rh-sso7-keycloak red hat single sign on 7.6 18.0.12-1.redhat_00001.1.el9sso
  • rh-sso7-keycloak-server red hat single sign on 7.6 18.0.12-1.redhat_00001.1.el9sso
  • rh-sso7-keycloak red hat single sign on 7.6 18.0.12-1.redhat_00001.1.el8sso
  • rh-sso7-keycloak-server red hat single sign on 7.6 18.0.12-1.redhat_00001.1.el8sso
  • rh-sso7-keycloak red hat single sign on 7.6 18.0.12-1.redhat_00001.1.el7sso
  • rh-sso7-keycloak-server red hat single sign on 7.6 18.0.12-1.redhat_00001.1.el7sso
  • rh-sso7-keycloak red hat single sign on 7.6 18.0.11-3.redhat_00001.1.el8sso
  • rh-sso7-keycloak-server red hat single sign on 7.6 18.0.11-3.redhat_00001.1.el8sso

red hat advisories RHSA-2024:0800RHSA-2024:0799RHSA-2024:0798RHSA-2024:0095RHSA-2024:0096RHSA-2024:0094

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-6927 updated cvss 4.6

keycloak: open redirect via "form_post.jwt" JARM response mode

  • Red Hat Middleware Containers for OpenShift rh-sso-7/sso76-openshift-rhel8 7.6-39, rh-sso-7/sso76-openshift-rhel8 7.6-41
    fixed: vendor fix RHSA-2024:0801
  • Red Hat build of Keycloak 22 rhbk/keycloak-rhel9 22-7
    fixed: vendor fix RHSA-2024:0100
  • Red Hat build of Keycloak 22.0.8
    fixed: vendor fix RHSA-2024:0101
  • Red Hat Single Sign-On 7
    fixed: vendor fix RHSA-2024:0804
  • Red Hat Single Sign-On 7.6 for RHEL 7 Server rh-sso7-keycloak 18.0.11-3.redhat_00001.1.el7sso, rh-sso7-keycloak 18.0.12-1.redhat_00001.1.el7sso, rh-sso7-keycloak-server 18.0.11-3.redhat_00001.1.el7sso, rh-sso7-keycloak-server 18.0.12-1.redhat_00001.1.el7sso
    fixed: vendor fix RHSA-2024:0094
  • Red Hat Single Sign-On 7.6 for RHEL 8 rh-sso7-keycloak 18.0.11-3.redhat_00001.1.el8sso, rh-sso7-keycloak 18.0.12-1.redhat_00001.1.el8sso, rh-sso7-keycloak-server 18.0.11-3.redhat_00001.1.el8sso, rh-sso7-keycloak-server 18.0.12-1.redhat_00001.1.el8sso
    fixed: vendor fix RHSA-2024:0095
  • Red Hat Single Sign-On 7.6 for RHEL 9 rh-sso7-keycloak 18.0.11-3.redhat_00001.1.el9sso, rh-sso7-keycloak 18.0.12-1.redhat_00001.1.el9sso, rh-sso7-keycloak-server 18.0.11-3.redhat_00001.1.el9sso, rh-sso7-keycloak-server 18.0.12-1.redhat_00001.1.el9sso
    fixed: vendor fix RHSA-2024:0096
  • Red Hat Single Sign-On 7.6.6
    fixed: vendor fix RHSA-2024:0098
show 1 more
  • Red Hat Middleware Containers for OpenShift rh-sso-7/sso7-rhel8-operator-bundle 7.6.6-3 Red Hat build of Keycloak 22 rhbk/keycloak-rhel9-operator 22-10, rhbk/keycloak-operator-bundle 22.0.8-1
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.11% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 4.6 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
GitHub 3.1 4.6 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
NVD 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected packages

ecosystem package affected fixed in
maven org.keycloak:keycloak-core
<23.0.4
23.0.4

Affected products

  • Red Hat Red Hat build of Keycloak 22
  • Red Hat Red Hat build of Keycloak 22.0.8
  • Red Hat Red Hat Single Sign-On 7
  • Red Hat Red Hat Single Sign-On 7.6 for RHEL 7
  • Red Hat Red Hat Single Sign-On 7.6 for RHEL 8
  • Red Hat Red Hat Single Sign-On 7.6 for RHEL 9
  • Red Hat RHEL-8 based Middleware Containers
  • Red Hat Single Sign-On 7.6.6

Classification

Weakness
  • CWE-601 URL Redirection to Untrusted Site

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Improve CPE configs to reflect keycloak upstream fixed at version 23.0.4.