CVE-2026-9087

HIGHNVD 8.16.4▼
EchelonGraph scoreMEDIUM confidence

Score 6.4 from GitHub Security Advisory published 2026-05-20. NVD baseline CVSS 8.1; sources differ by 1.7.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.1Exploit: NoneExposed: 0

A fix is available — apply it.

A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.

CVSS v3
8.1
EG Score
6.4(medium)
EPSS
23.0%
KEV
Not listed

Published

May 20, 2026

Last Modified

June 26, 2026

Advisory Details (2)

Auto-updated Jun 10, 2026
Patch available. Sources: redhat.
redhat

2480172 – (CVE-2026-9087) CVE-2026-9087 keycloak: Cross-Session Email Verification Proof Not Bound to Upstream Identity in First-Broker-Login

https://bugzilla.redhat.com/show_bug.cgi?id=2480172
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-9087

Vendor Advisories for CVE-2026-9087(5)

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

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatrhbk/keycloak-rhel92026-06-25redhat
redhatrhbk/keycloak-rhel9-operator:26.4-192026-06-25redhat
redhatrhbk/keycloak-rhel9-operator:26.6-62026-06-10redhat

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.

Affected Packages

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
org.keycloak:keycloak-services1.0-alpha-1 ... 9.0.3 (227 versions)26.6.3—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 65× 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. 2026-07-06 16:27 UTCEPSS rescore
  2. 2026-07-06 02:23 UTCEPSS rescore
  3. 2026-07-05 02:31 UTCEPSS rescore
  4. 2026-07-05 02:30 UTCEPSS rescore
  5. 2026-07-04 06:31 UTCEPSS rescore
  6. 2026-07-04 06:31 UTCEPSS rescore
  7. 2026-07-01 15:07 UTCEPSS rescore
  8. 2026-06-30 23:22 UTCEPSS rescore
  9. 2026-06-29 20:26 UTCEG score recompute
  10. 2026-06-29 20:26 UTCVendor advisory
  11. 2026-06-29 14:06 UTCEPSS rescore
  12. 2026-06-28 14:07 UTCEPSS rescore
  13. 2026-06-28 04:56 UTCEPSS rescore
  14. 2026-06-27 20:13 UTCEG score recompute
  15. 2026-06-27 20:13 UTCVendor advisory
  16. 2026-06-27 03:08 UTCEPSS rescore
  17. 2026-06-26 19:33 UTCEG score recompute
  18. 2026-06-26 19:33 UTCVendor advisory
  19. 2026-06-25 15:09 UTCEG score recompute
  20. 2026-06-25 15:09 UTCVendor advisory
  21. 2026-06-25 13:50 UTCEPSS rescore
  22. 2026-06-24 14:05 UTCEPSS rescore
  23. 2026-06-23 21:33 UTCEPSS rescore
  24. 2026-06-22 14:25 UTCEPSS rescore
  25. 2026-06-21 14:56 UTCEPSS rescore
Show 71 more
  1. 2026-06-21 01:59 UTCEPSS rescore
  2. 2026-06-19 19:26 UTCEPSS rescore
  3. 2026-06-18 17:52 UTCEPSS rescore
  4. 2026-06-18 02:02 UTCEG score recompute
  5. 2026-06-18 02:02 UTCVendor advisory
  6. 2026-06-17 17:53 UTCEPSS rescore
  7. 2026-06-17 00:30 UTCEG score recompute
  8. 2026-06-17 00:30 UTCVendor advisory
  9. 2026-06-16 17:53 UTCEPSS rescore
  10. 2026-06-16 00:37 UTCEG score recompute
  11. 2026-06-16 00:37 UTCVendor advisory
  12. 2026-06-15 17:49 UTCEPSS rescore
  13. 2026-06-15 17:49 UTCEPSS rescore
  14. 2026-06-15 00:46 UTCEG score recompute
  15. 2026-06-15 00:46 UTCVendor advisory
  16. 2026-06-14 23:18 UTCEPSS rescore
  17. 2026-06-14 00:52 UTCEG score recompute
  18. 2026-06-14 00:52 UTCVendor advisory
  19. 2026-06-13 23:00 UTCEPSS rescore
  20. 2026-06-13 01:02 UTCEG score recompute
  21. 2026-06-13 01:02 UTCVendor advisory
  22. 2026-06-12 23:12 UTCEPSS rescore
  23. 2026-06-12 23:12 UTCEPSS rescore
  24. 2026-06-12 01:10 UTCEG score recompute
  25. 2026-06-12 01:10 UTCVendor advisory
  26. 2026-06-11 14:00 UTCEPSS rescore
  27. 2026-06-11 01:19 UTCEG score recompute
  28. 2026-06-11 01:19 UTCVendor advisory
  29. 2026-06-11 01:19 UTCGHSA enrichment
  30. 2026-06-10 22:19 UTCEPSS rescore
  31. 2026-06-10 13:22 UTCEPSS rescore
  32. 2026-06-10 01:28 UTCEG score recompute
  33. 2026-06-10 01:28 UTCGHSA enrichment
  34. 2026-06-09 01:38 UTCEG score recompute
  35. 2026-06-09 01:38 UTCGHSA enrichment
  36. 2026-06-08 23:31 UTCNVD updateCVSS v3 → 8.1 · severity → HIGH
  37. 2026-06-08 14:17 UTCEPSS rescore
  38. 2026-06-08 01:47 UTCEG score recompute
  39. 2026-06-08 01:47 UTCGHSA enrichment
  40. 2026-06-07 15:25 UTCEPSS rescore
  41. 2026-06-07 01:57 UTCEG score recompute
  42. 2026-06-07 01:57 UTCGHSA enrichment
  43. 2026-06-06 13:47 UTCEPSS rescore
  44. 2026-06-06 02:06 UTCEG score recompute
  45. 2026-06-06 02:06 UTCGHSA enrichment
  46. 2026-06-05 22:47 UTCEPSS rescore
  47. 2026-06-05 06:10 UTCEPSS rescore
  48. 2026-06-05 02:16 UTCEG score recompute
  49. 2026-06-05 02:16 UTCGHSA enrichment
  50. 2026-06-04 13:12 UTCEPSS rescore
  51. 2026-06-04 02:25 UTCEG score recompute
  52. 2026-06-04 02:25 UTCGHSA enrichment
  53. 2026-06-03 02:33 UTCEG score recompute
  54. 2026-06-03 02:33 UTCGHSA enrichment
  55. 2026-06-02 20:13 UTCEPSS rescore
  56. 2026-06-02 02:42 UTCEG score recompute
  57. 2026-06-02 02:42 UTCGHSA enrichment
  58. 2026-06-01 13:52 UTCEPSS rescore
  59. 2026-06-01 02:51 UTCEG score recompute
  60. 2026-06-01 02:51 UTCGHSA enrichment
  61. 2026-05-31 22:30 UTCEPSS rescore
  62. 2026-05-31 00:16 UTCEPSS rescore
  63. 2026-05-29 13:44 UTCEPSS rescore
  64. 2026-05-28 13:44 UTCEPSS rescore
  65. 2026-05-27 13:40 UTCEPSS rescore
  66. 2026-05-26 13:44 UTCEPSS rescore
  67. 2026-05-26 07:18 UTCEPSS rescore
  68. 2026-05-23 00:07 UTCEG score recompute
  69. 2026-05-22 22:08 UTCEG score recompute
  70. 2026-05-21 22:43 UTCEPSS rescore
  71. 2026-05-20 17:36 UTCEG score recompute

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-9087?
CVE-2026-9087 is a high vulnerability published on May 20, 2026. A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.
When was CVE-2026-9087 disclosed?
CVE-2026-9087 was first published in the National Vulnerability Database on May 20, 2026, with the most recent update on June 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-9087 actively exploited?
CVE-2026-9087 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 23.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-9087?
CVE-2026-9087 has a CVSS v3 base score of 8.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 6.4.
How do I remediate CVE-2026-9087?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-9087, 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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