CVE-2026-18208

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreHIGH confidence

Score 6.5 from GitHub Security Advisory published 2026-07-31. a secondary CVSS source baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: None knownExposed: 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 OIDC token introspection endpoint of the keycloak-services component. Keycloak is an open-source identity and access management solution used to secure modern applications and services. The issue occurs when a confidential client, configured to receive signed JWT introspection responses, attempts to introspect a token issued for a different audience. Although the endpoint correctly identifies the token as inactive for that client, it still returns the full set of token claims within a signed JWT field. This allows an unauthorized client to bypass audience-based restrictions and access sensitive information contained in the token.

CVSS v3
6.5
EG Score
6.5(high)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity65% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
13%
KEV
Not listed

Published

July 31, 2026

Last Modified

July 31, 2026

Advisory Details (2)

Auto-updated Jul 31, 2026
Patch available. Sources: redhat.
redhat

2508304 – (CVE-2026-18208) CVE-2026-18208 keycloak-services: keycloak-services: Inactive out-of-audience token introspection leaks signed JWT claim

https://bugzilla.redhat.com/show_bug.cgi?id=2508304
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-18208

Vendor Advisories for CVE-2026-18208(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 11× in last 7d / 11× 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. 2026-08-02 02:26 UTCEPSS rescore
  2. 2026-08-01 22:47 UTCEG score recompute
  3. 2026-08-01 22:47 UTCGHSA enrichment
  4. 2026-08-01 04:15 UTCEPSS rescore
  5. 2026-07-31 20:23 UTCEG score recompute
  6. 2026-07-31 20:23 UTCGHSA enrichment
  7. 2026-07-31 19:48 UTCEG score recompute
  8. 2026-07-31 19:48 UTCGHSA enrichment
  9. 2026-07-31 08:18 UTCEG score recompute
  10. 2026-07-31 07:28 UTCEG score recompute
  11. 2026-07-31 07:28 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-18208?
CVE-2026-18208 is a medium vulnerability published on July 31, 2026. A flaw was found in the OIDC token introspection endpoint of the keycloak-services component. Keycloak is an open-source identity and access management solution used to secure modern applications and services. The issue occurs when a confidential client, configured to receive signed JWT…
When was CVE-2026-18208 disclosed?
CVE-2026-18208 was first published in the National Vulnerability Database on July 31, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18208 actively exploited?
CVE-2026-18208 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 87.2% of all scored CVEs.
What is the CVSS score of CVE-2026-18208?
CVE-2026-18208 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-18208?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-18208, 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

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