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.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-306"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/105xxx/CVE-2026-105207.json"
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "4.17.3"
},
{
"last_affected": "4.19.4"
}
],
"source": "AFFECTED_FIELD"
}