ZITADEL before 4.17.1 contains an authentication bypass vulnerability in Login V2 that allows unauthenticated attackers to take over accounts by obtaining OTP codes via the returnCode delivery type. Attackers knowing a login name of a victim with OTP-Email and OTP-SMS enrolled can read both codes from server-action responses to gain MFA-authenticated sessions, including administrator takeover.
CVE-2026-105211
HIGHPre-NVD 8.18.1—Trending — 3 sources updated this week
EchelonGraph scoreHIGH confidence
Score 8.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-10-04. A secondary CVSS source baseline 8.1; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 8.1Exploit: None knownExposed services: Not assessed
A fix is available — apply it.
- CVSS v3
- 8.1
- EG Score
- 8.1HIGHhigh confidence
- EG Risk
- 41EG Risk 41/100CISA 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 computedSeverity81% × 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 partial (CVSS below 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 4.17.1 Authentication Bypass via Login V2 OTP returnCode | Advisories | VulnCheck
https://www.vulncheck.com/advisories/zitadel-before-4.17.1-authentication-bypass-via-login-v2-otp-returncodegithub Patch Available
Unauthenticated account takeover via OTP-Email and OTP-SMS return-code bypass in Login V2 · Advisory · zitadel/zitadel · GitHub
https://github.com/zitadel/zitadel/security/advisories/GHSA-3gwm-5wx8-4gm6Vendor Advisories for CVE-2026-105211(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 5× in last 7d / 5× 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 04:20 UTCEG score recompute
- 2026-10-05 04:20 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-2026-105211?
CVE-2026-105211 is a high vulnerability published on October 4, 2026. ZITADEL before 4.17.1 contains an authentication bypass vulnerability in Login V2 that allows unauthenticated attackers to take over accounts by obtaining OTP codes via the returnCode delivery type. Attackers knowing a login name of a victim with OTP-Email and OTP-SMS enrolled can read both codes…
When was CVE-2026-105211 disclosed?
CVE-2026-105211 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-2026-105211?
CVE-2026-105211 has a CVSS base score of 8.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-105211?
A fix for CVE-2026-105211 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-105211 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-105211
Is Your Infrastructure Affected by CVE-2026-105211?
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