CVE-2026-105207CWE-306

CVE-2026-105207

Critical · published October 4, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
22.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
9.3 · 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
EPSS
0.00310 · 22.7th percentile
Weakness
CWE-306 · Missing Authentication for Critical Function
Published
2026-10-04T19:16Z
References (2)
https://github.com/zitadel/zitadel/security/advisories/GHSA-g8gj-gq47-xgf4 · [email protected]https://www.vulncheck.com/advisories/zitadel-before-4.17.3-account-takeover-via-external-idp-linking · [email protected]
EPSS history
Timeline
  • 07 OCT 03:39Z
    EPSS moved — → 0%
    epss
  • 04 OCT 13:10Z
    ZITADEL before 4.17.3 Account Takeover via External IdP Linking
    cvelistv5