CVE-2026-109372

critical

Description

ZITADEL 4.x before 4.19.2 and 3.x through 3.4.15 contains an authentication bypass in the SAML identity-provider intent callback, which verifies the assertion signature using the provider named in the request URL but resolves the user from the login intent without checking they match. Attackers with organization-administrator permission can register a SAML provider with their own signing key to obtain authenticated sessions as any user linked to another SAML provider on the instance, including in other organizations.

References

https://www.vulncheck.com/advisories/zitadel-3.0.0-before-4.19.2-account-takeover-via-saml-identity-provider-confusion

https://github.com/zitadel/zitadel/security/advisories/GHSA-x4c7-fpcx-w9q6

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-97670

Details

Source: Mitre, NVD

Published: 2026-10-12

Updated: 2026-10-13

Risk Information

CVSS v2

Base Score: 7.7

Vector: CVSS2#AV:N/AC:L/Au:M/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 8.7

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N

Severity: High

CVSS v4

Base Score: 9.3

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N

Severity: Critical

EPSS

EPSS: 0.0037