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TI-2021-02388 Aliases CVE-2021-3424GHSA-pf38-cw3p-22q9

Improper authentication in keycloak

Priority LOW 25CWE-287Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-287.

Summary

A flaw was found in keycloak as shipped in Red Hat Single Sign-On 7.4 where IDN homograph attacks are possible. A malicious user can register himself with a name already registered and trick admin to grant him extra privileges.

Why it matters now

EPSS 0.00774 55th percentileScored 2026-11-08
Fix Fixed org.keycloak:keycloak-services (Maven): 18.0.0Red Hat: 4 advisories

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—keycloakas shipped in Red Hat Single Sign-On 7.4—No fix listedCNA
—org.keycloak:keycloak-services (Maven)before 18.0.018.0.0Patch availableGHSA-pf38-cw3p-22q9
  • keycloak Vendor— Affected as shipped in Red Hat Single Sign-On 7.4 Fixed in — No fix listed CNA
  • org.keycloak:keycloak-services (Maven) Vendor— Affected before 18.0.0 Fixed in 18.0.0 Patch available GHSA-pf38-cw3p-22q9

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:redhat:single_sign-on:7.4:*:*:*:*:*:*:*7.4VulnerableRed Hat
  • cpe:2.3:a:redhat:single_sign-on:7.4:*:*:*:*:*:*:* Versions 7.4 Vulnerable ·Red Hat

Remediation

  • Fix · GHSA-pf38-cw3p-22q9 org.keycloak:keycloak-services (Maven) Fixed in 18.0.0 Advisory →

Red Hat 4 advisories

  • RHSA-2021:2070 Released 2021-05-20 · Red Hat rating Moderate
    Red Hat Single Sign-On 7.4.7 security update
    • Red Hat Single Sign-On 7.4.7
  • RHSA-2021:2064 Released 2021-05-20 · Red Hat rating Moderate
    Red Hat Single Sign-On 7.4.7 security update on RHEL 7
    • Red Hat Single Sign-On 7.4 for RHEL 7 Server rh-sso7-keycloak-9.0.13-1.redhat_00006.1.el7sso, rh-sso7-keycloak-server-9.0.13-1.redhat_00006.1.el7sso
  • RHSA-2021:2065 Released 2021-05-20 · Red Hat rating Moderate
    Red Hat Single Sign-On 7.4.7 security update on RHEL 8
    • Red Hat Single Sign-On 7.4 for RHEL 8 rh-sso7-keycloak-9.0.13-1.redhat_00006.1.el8sso, rh-sso7-keycloak-server-9.0.13-1.redhat_00006.1.el8sso
Show 1 more Red Hat advisories
  • RHSA-2021:2063 Released 2021-05-20 · Red Hat rating Moderate
    Red Hat Single Sign-On 7.4.7 security update on RHEL 6
    • Red Hat Single Sign-On 7.4 for RHEL 6 Server rh-sso7-keycloak-9.0.13-1.redhat_00006.1.el6sso, rh-sso7-keycloak-server-9.0.13-1.redhat_00006.1.el6sso

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Single Sign-On 7.4 for RHEL 6 ServerFixed RHSA-2021:2063
Red Hat Single Sign-On 7.4 for RHEL 7 ServerFixed RHSA-2021:2064
Red Hat Single Sign-On 7.4 for RHEL 8Fixed RHSA-2021:2065
Red Hat Single Sign-On 7.4.7Fixed RHSA-2021:2070
Not affected: 6 products
  • Red Hat Decision Manager 7
  • Red Hat Fuse 7
  • Red Hat Integration Camel K 1
  • Red Hat OpenShift Application Runtimes
  • Red Hat Process Automation 7
  • Red Hat support for Spring Boot

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-3424
  2. 2026-10-03 Alias added: GHSA-pf38-cw3p-22q9

References

Advisory 2

Other 1

  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2025-11507 Undertow-core: undertow http server fails to reject malformed host headers leading to potential cache poisoning and ssrf CVSS 3.1CRITICAL 9.6
  • TI-2019-06950 Some HTTP/2 implementations are vulnerable to a settings flood, potentially leading to a… CVSS 3.1HIGH 7.5
  • TI-2019-06949 Some HTTP/2 implementations are vulnerable to a reset flood, potentially leading to a… CVSS 3.1HIGH 7.5
  • TI-2021-02983 Deserialization of untrusted data in JMSAppender in Apache Log4j 1.2 CVSS 3.1HIGH 7.5
  • TI-2024-01049 Keycloak: path transversal in redirection validation CVSS 3.1HIGH 8.1
See all 112 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences