high8.1
CVE-2026-56668
ZITADEL: Unauthorized Token Privilege Escalation in OAuth2 Token Exchange
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/zitadel/zitadel | < 4.15.3 | 4.15.3 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-vrh8-c9cm-wh8v
- https://github.com/zitadel/zitadel/security/advisories/GHSA-vrh8-c9cm-wh8v
- https://nvd.nist.gov/vuln/detail/CVE-2026-56668
- https://github.com/zitadel/zitadel/commit/e2886a61670ca8fd41c9434f87036546e5620bcc
- https://github.com/zitadel/zitadel/releases/tag/v4.15.3