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.
CVE-2026-56668
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).
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.1
- EG Score
- 8.1(medium)
- EPSS
- 13.8%
- KEV
- Not listed
Published
July 10, 2026
Last Modified
July 14, 2026
Advisory Details (3)
Auto-updated Jul 10, 2026Unauthorized Token Privilege Escalation in OAuth2 Token Exchange · Advisory · zitadel/zitadel · GitHub
https://github.com/zitadel/zitadel/security/advisories/GHSA-vrh8-c9cm-wh8vv4.15.3
Patch available: zitadel/zitadel v4.15.3
https://github.com/zitadel/zitadel/releases/tag/v4.15.3commit e2886a61670c (zitadel/zitadel)
Fix landed in zitadel/zitadel commit e2886a61670c — awaiting tagged release
https://github.com/zitadel/zitadel/commit/e2886a61670ca8fd41c9434f87036546e5620bccWeakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 20× in last 7d / 20× 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.
- 2026-07-15 18:56 UTCEG score recompute
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-15 06:50 UTCEG score recompute
- 2026-07-15 02:00 UTCEPSS rescore
- 2026-07-15 02:00 UTCEPSS rescore
- 2026-07-14 18:45 UTCEG score recompute
- 2026-07-14 06:38 UTCEG score recompute
- 2026-07-13 22:31 UTCEPSS rescore
- 2026-07-13 18:31 UTCEG score recompute
- 2026-07-13 06:25 UTCEG score recompute
- 2026-07-13 06:13 UTCEPSS rescore
- 2026-07-13 06:13 UTCEPSS rescore
- 2026-07-12 18:17 UTCEG score recompute
- 2026-07-12 06:12 UTCEG score recompute
- 2026-07-12 05:46 UTCEPSS rescore
- 2026-07-11 18:04 UTCEG score recompute
- 2026-07-11 05:59 UTCEG score recompute
- 2026-07-10 17:53 UTCEG score recompute
- 2026-07-10 17:52 UTCMITRE cvelistV5first tracked
Frequently asked(5)
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Dependency Blast Radius
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