CVE-2026-105207

critical

Description

ZITADEL 3.0.0 through 3.4.15 and 4.0.0 before 4.17.3 creates links between user accounts and external identity providers without verifying a primary factor or the caller's permission, including on identify-only Login V2 sessions and via the User Service V2 AddIDPLink endpoint. An unauthenticated attacker knowing a victim's login name can bind their own external IdP identity to the victim's account and then sign in as the victim.

References

https://www.vulncheck.com/advisories/zitadel-before-4.17.3-account-takeover-via-external-idp-linking

https://github.com/zitadel/zitadel/security/advisories/GHSA-g8gj-gq47-xgf4

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-92100

Details

Source: Mitre, NVD

Published: 2026-10-04

Updated: 2026-10-29

Risk Information

CVSS v2

Base Score: 10

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

Severity: Critical

CVSS v3

Base Score: 9.8

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

Severity: Critical

CVSS v4

Base Score: 9.3

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

Severity: Critical

EPSS

EPSS: 0.0031