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CVE-2026-96453NVD status: Awaiting Analysis

Red Hat build of Keycloak 26.4: Improper Certificate Validation

CVE-2026-96453 is a high-severity improper certificate validation vulnerability in Red Hat build of Keycloak 26.4 from Red Hat, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. There is no confirmed exploitation so far. EPSS estimates a 0.22% 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.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

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 AMQ Broker 7Not specified in the recordNot stated
Red HatRed Hat Fuse 7Not specified in the recordNot stated
Red HatRed Hat JBoss Enterprise Application Platform 7Not specified in the recordNot stated
Red HatRed Hat JBoss Enterprise Application Platform 8Not specified in the recordNot stated
Red HatRed Hat JBoss Enterprise Application Platform Expansion PackNot specified in the recordNot stated
Red HatRed Hat Satellite 6Not 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
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

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

Official description

A flaw was found in the Keycloak Admin CLI kcadm tool, which is used by administrators to manage Keycloak servers from the command line. When a custom truststore is provided to verify the server identity, the tool incorrectly accepts any self-signed certificate as long as the hostname matches. This allows a network attacker to impersonate the Keycloak server, steal administrative credentials, and perform unauthorized management actions.

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

The underlying weakness: Improper Certificate Validation

The product does not validate, or incorrectly validates, a certificate.

How developers prevent this class of flaw

  • Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
  • If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.

More Improper Certificate Validation vulnerabilities (CWE-295)

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 Certificate Validation vulnerabilities

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