CyberSecBulletin
CVE-2026-3047NVD status: Modified

Red Hat build of Keycloak 26.2: Authentication Bypass by Primary Weakness

CVE-2026-3047 is a high-severity authentication bypass by primary weakness vulnerability in Red Hat build of Keycloak 26.2 from Red Hat, with a CVSS 3.1 base score of 8.8 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 0.55% 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 26.2 you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on access.redhat.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Red HatRed Hat build of Keycloak 26.2Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.2.14Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.4Not specified in the recordNot stated
Red HatRed Hat build of Keycloak 26.4.10Not specified in the recordNot stated
Red HatBuild Of Keycloak26.2; 26.2.14; 26.4; 26.4.10Not stated
Red HatKeycloakNot 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
LowNo special conditions are needed; the attack works reliably.
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
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighCNA (redhat.com)
CVSS 3.18.8HighCNA

Official description

A flaw was found in org.keycloak.broker.saml. When a disabled Security Assertion Markup Language (SAML) client is configured as an Identity Provider (IdP)-initiated broker landing target, it can still complete the login process and establish a Single Sign-On (SSO) session. This allows a remote attacker to gain unauthorized access to other enabled clients without re-authentication, effectively bypassing security restrictions.

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

The underlying weakness: Authentication Bypass by Primary Weakness

The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error.

More Authentication Bypass by Primary Weakness vulnerabilities (CWE-305)

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 26.2

All Red Hat build of Keycloak 26.2 vulnerabilities

Recent Authentication Bypass by Primary Weakness vulnerabilities

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