CVE-2026-56668

HIGHPre-NVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 86% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
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

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

ZITADEL is an open source identity management platform. Prior to 4.15.3, ZITADEL's OAuth2 Token Exchange endpoint for urn:ietf:params:oauth:grant-type:token-exchange does not verify that the subject token belongs to the requesting client or that requested scopes remain within the original token's scopes, allowing a low-privilege token to be exchanged for elevated permissions at another application. This issue is fixed in version 4.15.3.

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 10, 2026

Last Modified

July 14, 2026

Advisory Details (3)

Auto-updated Jul 10, 2026
Patch available. Sources: github_commit, github_release, github.
github Patch Available

Unauthorized Token Privilege Escalation in OAuth2 Token Exchange · Advisory · zitadel/zitadel · GitHub

https://github.com/zitadel/zitadel/security/advisories/GHSA-vrh8-c9cm-wh8v
github_release Patch Available

v4.15.3

Patch available: zitadel/zitadel v4.15.3

https://github.com/zitadel/zitadel/releases/tag/v4.15.3
github_commit

commit e2886a61670c (zitadel/zitadel)

Fix landed in zitadel/zitadel commit e2886a61670c — awaiting tagged release

https://github.com/zitadel/zitadel/commit/e2886a61670ca8fd41c9434f87036546e5620bcc

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 14× in last 7d / 42× 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. 2026-08-03 14:14 UTCEG score recompute
  2. 2026-08-03 10:36 UTCEPSS rescore
  3. 2026-08-02 13:59 UTCEG score recompute
  4. 2026-08-02 02:27 UTCEPSS rescore
  5. 2026-08-01 13:49 UTCEG score recompute
  6. 2026-08-01 04:16 UTCEPSS rescore
  7. 2026-07-31 01:24 UTCEG score recompute
  8. 2026-07-30 16:28 UTCEPSS rescore
  9. 2026-07-30 13:18 UTCEG score recompute
  10. 2026-07-30 01:30 UTCEPSS rescore
  11. 2026-07-30 01:30 UTCEPSS rescore
  12. 2026-07-29 00:44 UTCEG score recompute
  13. 2026-07-28 15:37 UTCEPSS rescore
  14. 2026-07-28 00:32 UTCEG score recompute
  15. 2026-07-27 14:14 UTCEPSS rescore
  16. 2026-07-27 00:16 UTCEG score recompute
  17. 2026-07-26 14:54 UTCEPSS rescore
  18. 2026-07-26 14:54 UTCEPSS rescore
  19. 2026-07-26 12:10 UTCEG score recompute
  20. 2026-07-25 14:18 UTCEPSS rescore
  21. 2026-07-25 14:18 UTCEPSS rescore
  22. 2026-07-24 14:18 UTCEPSS rescore
  23. 2026-07-23 14:18 UTCEPSS rescore
  24. 2026-07-23 03:20 UTCEG score recompute
  25. 2026-07-22 14:08 UTCEPSS rescore
Show 17 more
  1. 2026-07-21 15:25 UTCEPSS rescore
  2. 2026-07-20 17:08 UTCEPSS rescore
  3. 2026-07-19 14:31 UTCEPSS rescore
  4. 2026-07-19 14:31 UTCEPSS rescore
  5. 2026-07-19 02:29 UTCEPSS rescore
  6. 2026-07-18 10:04 UTCEPSS rescore
  7. 2026-07-16 17:03 UTCEPSS rescore
  8. 2026-07-15 16:57 UTCEPSS rescore
  9. 2026-07-15 16:57 UTCEPSS rescore
  10. 2026-07-15 02:00 UTCEPSS rescore
  11. 2026-07-15 02:00 UTCEPSS rescore
  12. 2026-07-13 22:31 UTCEPSS rescore
  13. 2026-07-13 06:13 UTCEPSS rescore
  14. 2026-07-13 06:13 UTCEPSS rescore
  15. 2026-07-12 05:46 UTCEPSS rescore
  16. 2026-07-10 17:53 UTCEG score recompute
  17. 2026-07-10 17:52 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-56668?
CVE-2026-56668 is a high vulnerability published on July 10, 2026. ZITADEL is an open source identity management platform. Prior to 4.15.3, ZITADEL's OAuth2 Token Exchange endpoint for urn:ietf:params:oauth:grant-type:token-exchange does not verify that the subject token belongs to the requesting client or that requested scopes remain within the original token's…
When was CVE-2026-56668 disclosed?
CVE-2026-56668 was first published in the National Vulnerability Database on July 10, 2026, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56668 actively exploited?
CVE-2026-56668 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 86.0% of all scored CVEs.
What is the CVSS score of CVE-2026-56668?
CVE-2026-56668 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-56668?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56668, 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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