CVE-2026-16103

MEDIUMPre-NVD 4.34.3—
EchelonGraph scoreHIGH confidence

Score 4.3 from GitHub Security Advisory published 2026-07-17. a secondary CVSS source baseline 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
Trending — 4 sources updated this week
4.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 4.3Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix for CVE-2026-9798, where brute-force protection checks were added to the Client-Initiated Backchannel Authentication (CIBA) initiation handler but were omitted from the token redemption handler. This allows an attacker with valid client credentials to obtain access and refresh tokens for a user account that has been locked due to brute-force protection, provided the authentication request was started before the lockout occurred and was approved by the user.

CVSS v3
4.3
EG Score
4.3(high)
EPSS
10.9%
KEV
Not listed

Published

July 17, 2026

Last Modified

July 21, 2026

Advisory Details (2)

Auto-updated Jul 17, 2026
Patch available. Sources: redhat.
redhat

2501736 – (CVE-2026-16103) CVE-2026-16103 keycloak-services: keycloak-services: Incomplete fix for CIBA brute-force lockout bypass at token redemption

https://bugzilla.redhat.com/show_bug.cgi?id=2501736
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-16103

Vendor Advisories for CVE-2026-16103(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 10× in last 7d / 10× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-21 15:24 UTCEPSS rescore
  3. 2026-07-20 17:08 UTCEPSS rescore
  4. 2026-07-19 14:30 UTCEPSS rescore
  5. 2026-07-19 02:28 UTCEPSS rescore
  6. 2026-07-17 20:02 UTCEG score recompute
  7. 2026-07-17 20:02 UTCGHSA enrichment
  8. 2026-07-17 18:01 UTCEG score recompute
  9. 2026-07-17 16:46 UTCEG score recompute
  10. 2026-07-17 16:44 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-16103?
CVE-2026-16103 is a medium vulnerability published on July 17, 2026. A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix for CVE-2026-9798, where brute-force protection checks were added to the Client-Initiated Backchannel Authentication (CIBA) initiation handler but were omitted from the token redemption handler. This…
When was CVE-2026-16103 disclosed?
CVE-2026-16103 was first published in the National Vulnerability Database on July 17, 2026, with the most recent update on July 21, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-16103 actively exploited?
CVE-2026-16103 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 10.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-16103?
CVE-2026-16103 has a CVSS v3 base score of 4.3 (NVD).
How do I remediate CVE-2026-16103?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-16103, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-16103

Explore →

Is Your Infrastructure Affected by CVE-2026-16103?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs