Vulnerability · Published Sep 24, 2026 · Assigned by GitHub_M
CVE-2026-85056ZITADEL: MFA bypass via session reuse in Login V2
High 8.2
In plain English
A high-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.
Official description
ZITADEL is an open source identity management platform. From 4.0.0 until 4.16.1, ZITADEL Login V2 creates a browser session after password verification and can reuse that session for a later authentication request without verifying a user's enrolled TOTP, OTP, or U2F second factor. When the MFA step is abandoned and login starts again, session-validity checks require MFA only when the organization enables Force MFA or Force MFA for local users only, so a voluntarily enrolled factor can be skipped while completing an OIDC or SAML callback for a customer application. Login V1, the ZITADEL Console, Management and Admin APIs, and user self-management are not affected. This issue is fixed in version 4.16.1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/zitadel/zitadel | 1.80.0-v2.20.0.20260717062356-56f4798ed31f | GHSA-9993-rfwp-rhwf |
| Go | github.com/zitadel/zitadel | 1.80.0-v2.20.0.20260717062356-56f4798ed31f | GO-2026-6589 |
Affected products (as reported)
Weakness: CWE-287 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
References
- https://github.com/zitadel/zitadel/security/advisories/GHSA-9993-rfwp-rhwf x_refsource_CONFIRM
- https://github.com/zitadel/zitadel/commit/049dbb25a56587fb3980c85c99819cad69f637db x_refsource_MISC
- https://github.com/zitadel/zitadel/commit/56f4798ed31fc1cfcd9a0e7f6f0152289d2fdc43 x_refsource_MISC
- https://github.com/zitadel/zitadel/releases/tag/v4.16.1 x_refsource_MISC