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CVE-2026-97847NVD status: Awaiting Analysis

Red Hat build of Keycloak 26.4: Improper Authentication

CVE-2026-97847 is a high-severity improper authentication vulnerability in Red Hat build of Keycloak 26.4 from Red Hat, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 0.32% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Red Hat build of Keycloak 26.4 you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
Red HatRed Hat build of Keycloak 26.4Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.4.17Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.6Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.6.8Not specified in the recordNot stated
Red HatRed Hat Single Sign-On 7Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L. Scored by CNA (redhat.com).

Official description

A flaw was found in the protocol mapper and identity resolution components of Keycloak. The issue occurs when a client manager uses hardcoded-claim mappers to override identity claims in sessionless service-account tokens. Because these tokens lack a session ID, Keycloak may incorrectly resolve the token bearer as a different, highly privileged user based on the manipulated claims. This can allow an attacker with limited client management permissions to impersonate a realm administrator and gain full control over the realm.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

How developers prevent this class of flaw

  • Use an authentication framework or library such as the OWASP ESAPI Authentication feature.

More Improper Authentication vulnerabilities (CWE-287)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Red Hat build of Keycloak 26.4

All Red Hat build of Keycloak 26.4 vulnerabilities

Recent Improper Authentication vulnerabilities

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