CVE-2026-16103Network attack vector

Locked-account session access via omitted redemption check

Published Jul 17, 2026 · Updated Jul 17, 2026

Authentication bypass in Red Hat build of Keycloak allows remote authenticated users to redeem approved CIBA requests for locked accounts. The CIBA grant redemption code path issues access and refresh tokens without repeating the brute-force protector check applied at request initiation. Exploitation requires valid client credentials and a user-approved request initiated before lockout, and yields a session for the temporarily locked account.

CVSS severity4.3
Medium
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Red Hat build of Keycloak allows remote authenticated users to redeem approved CIBA requests for locked accounts. The CIBA grant redemption code path issues access and refresh tokens without repeating the brute-force protector check applied at request initiation. Exploitation requires valid client credentials and a user-approved request initiated before lockout, and yields a session for the temporarily locked account.

The record

CVE
CVE-2026-16103
Published
Jul 17, 2026
Updated
Jul 17, 2026
Vendor
389 Directory Server
Product
Red Hat build of Keycloak
Classifications
CWE-841, T1550.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 17, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

389 Directory Server · Red Hat build of KeycloakAffected versions are unavailable in this record.

Published CVSS scores

4.3Red Hat, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-841Improper Enforcement of Behavioral Workflow
T1550.001Application Access Token

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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