CVE-2026-56666 json
ZITADEL: Auto-linking by email: IdP-side email verification is not checked
published 4mo ago modified last mo. also EUVD-2026-42966 , GHSA-992q-9gwp-7r79 , GO-2026-6470
- cvss
- 4.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
ZITADEL is an open source identity management platform. Prior to 4.15.3, ZITADEL's external identity provider handler checks that the local user's email is verified but does not verify that the external IdP confirmed ownership of the same email before auto-linking by email, allowing a permissive provider account with a victim email address to be linked to the victim's local account. This issue is fixed in version 4.15.3.
Patch / fix
- go github.com/zitadel/zitadel 4.15.3
- zitadel zitadel 4.15.3
- govulncheck-vulndb SLES 16.0, SLES for SAP applications 16.0 0.0.20260916T180043-160000.1.1
suse advisories SUSE-SU-2026:23855-1SUSE-SU-2026:23863-1
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260916T180043-160000.1.1
opensuse advisories openSUSE-SU-2026:21897-1
Is CVE-2026-56666 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 3mo ago
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |
| GitHub | 3.1 | 4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/zitadel/zitadel | <4.15.3 all versions |
4.15.3 |
Affected products
- zitadel zitadel
Classification
- Weakness
-
- CWE-287 Improper Authentication
References
-
github.com
/zitadel/zitadel/commit/c97012f0c5dc2fe960ae6e940cbea23229f0557f
web, patch
-
github.com
/zitadel/zitadel/security/advisories/GHSA-992q-9gwp-7r79
web, advisory
-
github.com
/zitadel/zitadel/releases/tag/v4.15.3
web
-
nvd.nist.gov
/vuln/detail/CVE-2026-56666
advisory
-
github.com
/zitadel/zitadel
package
Sources
- CVE List CVE-2026-56666
- GitHub Advisory GHSA-992q-9gwp-7r79
- NVD CVE-2026-56666
- OSV GO-2026-6470
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.