Vulnerability · Published Jul 10, 2026 · Assigned by GitHub_M

CVE-2026-56666ZITADEL: Auto-linking by email: IdP-side email verification is not checked

Medium 4.8

In plain English

A medium-severity improper authentication in zitadel from zitadel. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.8Medium

Exploit odds (30 days)0.3%top 78.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/zitadel/zitadel	4.15.3	GHSA-992q-9gwp-7r79
Go	github.com/zitadel/zitadel	no fix listed	GO-2026-6470

Affected products (as reported)

Vendor	Product	Versions
zitadel	zitadel	< 4.15.3

Weakness: CWE-287 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

References

https://github.com/zitadel/zitadel/security/advisories/GHSA-992q-9gwp-7r79 x_refsource_CONFIRM
https://github.com/zitadel/zitadel/commit/c97012f0c5dc2fe960ae6e940cbea23229f0557f x_refsource_MISC
https://github.com/zitadel/zitadel/releases/tag/v4.15.3 x_refsource_MISC