CVE-2026-18215

HIGHNVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.1 under NVD CVSS v3. EPSS exploit probability: 0.2%, top 86% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.

Triggered by: NVD CVSS baseline
Sources: epss, ghsa, nvd
Trending — Patch released this week
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.1Exploit: None knownExposed: 0

A fix is available — apply it.

Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization (tenant). A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely different organization could gain access to the Keycloak realm, potentially accessing sensitive data or performing unauthorized actions.

CVSS v3
8.1
EG Score
8.1(medium)
EG Risk
37(Track)
EG Risk 37/100SSVC: 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
Severity81% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
14%
KEV
Not listed

Published

July 31, 2026

Last Modified

September 16, 2026

Advisory Details (2)

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

2508309 – (CVE-2026-18215) CVE-2026-18215 keycloak-services: keycloak-services: Microsoft external access-token exchange bypasses configured tenant

https://bugzilla.redhat.com/show_bug.cgi?id=2508309
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-18215

Vendor Advisories for CVE-2026-18215(2)

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

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatrhbk/keycloak-rhel9-operator:26.6-202026-09-16redhat
redhatrhbk-openshift-rhel9/rhbk-openshift-rhel92026-09-16redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 29× in last 7d / 101× 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.

Showing the most recent 100 of 182 total refreshes for this CVE.

  1. 2026-09-19 00:37 UTCEG score recompute
  2. 2026-09-19 00:37 UTCVendor advisory
  3. 2026-09-19 00:37 UTCGHSA enrichment
  4. 2026-09-18 19:27 UTCEPSS rescore
  5. 2026-09-18 13:31 UTCVendor advisory
  6. 2026-09-18 13:31 UTCGHSA enrichment
  7. 2026-09-18 01:17 UTCEG score recompute
  8. 2026-09-18 01:17 UTCVendor advisory
  9. 2026-09-18 01:17 UTCGHSA enrichment
  10. 2026-09-17 07:07 UTCGHSA enrichment
  11. 2026-09-16 19:20 UTCGHSA enrichment
  12. 2026-09-16 18:41 UTCGHSA enrichment
  13. 2026-09-16 17:11 UTCGHSA enrichment
  14. 2026-09-16 15:55 UTCEG score recompute
  15. 2026-09-16 15:55 UTCGHSA enrichment
  16. 2026-09-16 14:07 UTCEPSS rescore
  17. 2026-09-16 05:29 UTCEG score recompute
  18. 2026-09-16 05:29 UTCGHSA enrichment
  19. 2026-09-16 05:14 UTCEPSS rescore
  20. 2026-09-15 03:04 UTCGHSA enrichment
  21. 2026-09-14 09:43 UTCGHSA enrichment
  22. 2026-09-13 22:34 UTCEG score recompute
  23. 2026-09-13 22:34 UTCGHSA enrichment
  24. 2026-09-13 16:46 UTCEPSS rescore
  25. 2026-09-13 11:28 UTCGHSA enrichment
Show 75 more
  1. 2026-09-13 00:22 UTCEG score recompute
  2. 2026-09-13 00:22 UTCGHSA enrichment
  3. 2026-09-12 15:00 UTCEPSS rescore
  4. 2026-09-12 13:11 UTCGHSA enrichment
  5. 2026-09-12 02:04 UTCGHSA enrichment
  6. 2026-09-11 14:58 UTCEG score recompute
  7. 2026-09-11 14:58 UTCGHSA enrichment
  8. 2026-09-11 14:52 UTCEPSS rescore
  9. 2026-09-11 09:36 UTCEPSS rescore
  10. 2026-09-11 01:38 UTCGHSA enrichment
  11. 2026-09-10 14:29 UTCEG score recompute
  12. 2026-09-10 14:29 UTCGHSA enrichment
  13. 2026-09-10 09:34 UTCEPSS rescore
  14. 2026-09-10 03:23 UTCGHSA enrichment
  15. 2026-09-09 07:07 UTCEG score recompute
  16. 2026-09-09 07:06 UTCGHSA enrichment
  17. 2026-09-08 22:00 UTCEPSS rescore
  18. 2026-09-07 19:37 UTCEG score recompute
  19. 2026-09-07 19:37 UTCGHSA enrichment
  20. 2026-09-07 16:01 UTCEPSS rescore
  21. 2026-09-06 17:02 UTCEG score recompute
  22. 2026-09-06 17:02 UTCGHSA enrichment
  23. 2026-09-06 13:47 UTCEPSS rescore
  24. 2026-09-06 05:56 UTCGHSA enrichment
  25. 2026-09-05 18:47 UTCEG score recompute
  26. 2026-09-05 18:47 UTCGHSA enrichment
  27. 2026-09-05 04:46 UTCEG score recompute
  28. 2026-09-05 04:46 UTCGHSA enrichment
  29. 2026-09-04 11:21 UTCEG score recompute
  30. 2026-09-04 11:21 UTCGHSA enrichment
  31. 2026-09-04 05:06 UTCEPSS rescore
  32. 2026-09-03 21:12 UTCGHSA enrichment
  33. 2026-09-03 09:13 UTCEG score recompute
  34. 2026-09-03 09:13 UTCGHSA enrichment
  35. 2026-09-02 14:11 UTCEPSS rescore
  36. 2026-09-01 22:34 UTCEG score recompute
  37. 2026-09-01 22:34 UTCGHSA enrichment
  38. 2026-09-01 13:53 UTCEPSS rescore
  39. 2026-09-01 04:39 UTCEPSS rescore
  40. 2026-09-01 02:56 UTCGHSA enrichment
  41. 2026-08-31 15:39 UTCGHSA enrichment
  42. 2026-08-30 21:16 UTCEG score recompute
  43. 2026-08-30 21:16 UTCGHSA enrichment
  44. 2026-08-30 19:17 UTCEPSS rescore
  45. 2026-08-30 10:10 UTCEG score recompute
  46. 2026-08-30 10:10 UTCGHSA enrichment
  47. 2026-08-30 01:22 UTCEPSS rescore
  48. 2026-08-29 22:23 UTCEG score recompute
  49. 2026-08-29 22:23 UTCGHSA enrichment
  50. 2026-08-28 21:41 UTCEPSS rescore
  51. 2026-08-27 20:46 UTCGHSA enrichment
  52. 2026-08-27 08:50 UTCGHSA enrichment
  53. 2026-08-26 19:16 UTCEG score recompute
  54. 2026-08-26 19:16 UTCGHSA enrichment
  55. 2026-08-26 14:46 UTCEPSS rescore
  56. 2026-08-26 06:57 UTCGHSA enrichment
  57. 2026-08-25 19:51 UTCEG score recompute
  58. 2026-08-25 19:51 UTCGHSA enrichment
  59. 2026-08-25 13:48 UTCEPSS rescore
  60. 2026-08-25 08:45 UTCGHSA enrichment
  61. 2026-08-24 21:40 UTCEG score recompute
  62. 2026-08-24 21:40 UTCGHSA enrichment
  63. 2026-08-24 10:26 UTCEG score recompute
  64. 2026-08-24 10:26 UTCGHSA enrichment
  65. 2026-08-23 23:20 UTCGHSA enrichment
  66. 2026-08-23 12:15 UTCGHSA enrichment
  67. 2026-08-23 01:09 UTCGHSA enrichment
  68. 2026-08-22 14:02 UTCGHSA enrichment
  69. 2026-08-22 02:56 UTCEG score recompute
  70. 2026-08-22 02:56 UTCGHSA enrichment
  71. 2026-08-21 23:49 UTCEPSS rescore
  72. 2026-08-21 15:50 UTCGHSA enrichment
  73. 2026-08-21 04:44 UTCEG score recompute
  74. 2026-08-21 04:44 UTCGHSA enrichment
  75. 2026-08-20 22:55 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-18215?
CVE-2026-18215 is a high vulnerability published on July 31, 2026. Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization (tenant). A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely…
When was CVE-2026-18215 disclosed?
CVE-2026-18215 was first published in the National Vulnerability Database on July 31, 2026, with the most recent update on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18215 actively exploited?
CVE-2026-18215 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 86.4% of all scored CVEs.
What is the CVSS score of CVE-2026-18215?
CVE-2026-18215 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-18215?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-18215, 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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