ZITADEL before 3.4.14 and 4.x before 4.16.2 contains an authentication bypass in the hosted Login V1 UI because the 'external account not found' registration endpoint trusts client-supplied external identity fields without a completed IdP callback. Unauthenticated attackers can submit forged IDPConfigID and ExternalUserID values to pre-create an account bound to a victim's external IdP identity, which the victim's later genuine external login then signs into.
CVE-2026-105215
CRITICALPre-NVD 9.19.1—Trending — 3 sources updated this week
EchelonGraph scoreHIGH confidence
Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-10-04. A secondary CVSS source baseline 9.1; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 9.1Exploit: None knownExposed services: Not assessed
A fix is available — apply it.
- CVSS v3
- 9.1
- EG Score
- 9.1CRITICALhigh confidence
- EG Risk
- 45EG Risk 45/100CISA SSVC
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity91% × 45%Exploitation0% × 40%Automatability30% × 15%CISA SSVC: Track at low or medium mission impact; Track* or Attend at high (mission-essential systems).Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high. - EPSS PROB
- —
- EPSS %ILE
- —
- KEV
- Not listed
CISA SSVCTrack at low or medium mission impact; Track* or Attend at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation none (no KEV listing, exploit record or EPSS ≥ 50%) · Automatable unknown (not published for this CVE) · Technical impact total (CVSS ≥ 9.0). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
October 4, 2026
Last Modified
October 4, 2026
Advisory Details (2)
Auto-updated Oct 4, 2026Patch available. Sources: github.
generic
ZITADEL before 4.16.2 Account Pre-Hijacking via Forged External IdP Callback | Advisories | VulnCheck
https://www.vulncheck.com/advisories/zitadel-before-4.16.2-account-pre-hijacking-via-forged-external-idp-callbackgithub Patch Available
Unauthenticated Account Pre-Hijacking via Forged External Identity Provider Callback in Login V1 · Advisory · zitadel/zitadel · GitHub
https://github.com/zitadel/zitadel/security/advisories/GHSA-738m-7888-jfv8Vendor Advisories for CVE-2026-105215(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 9× in last 7d / 9× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-10-05 11:10 UTCGHSA enrichment
- 2026-10-05 07:13 UTCGHSA enrichment
- 2026-10-05 03:16 UTCGHSA enrichment
- 2026-10-04 23:19 UTCGHSA enrichment
- 2026-10-04 19:21 UTCEG score recompute
- 2026-10-04 19:21 UTCGHSA enrichment
- 2026-10-04 15:24 UTCEG score recompute
- 2026-10-04 14:29 UTCEG score recompute
- 2026-10-04 14:28 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(4)
What is CVE-2026-105215?
CVE-2026-105215 is a critical vulnerability published on October 4, 2026. ZITADEL before 3.4.14 and 4.x before 4.16.2 contains an authentication bypass in the hosted Login V1 UI because the 'external account not found' registration endpoint trusts client-supplied external identity fields without a completed IdP callback. Unauthenticated attackers can submit forged…
When was CVE-2026-105215 disclosed?
CVE-2026-105215 was first published on October 4, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-105215?
CVE-2026-105215 has a CVSS base score of 9.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-105215?
A fix for CVE-2026-105215 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-105215 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-105215
Is Your Infrastructure Affected by CVE-2026-105215?
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