CVE-2026-105211 ZITADEL before 4.17.1 Authentication Bypass via Login V2 OTP returnCode
Unauthenticated attackers can bypass MFA and take over accounts, including administrators, by reading OTP codes from server responses.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-105211?
CVE-2026-105211 is a critical authentication bypass vulnerability in zitadel, published on 4 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-200
Which versions are affected by CVE-2026-105211?
How do I fix CVE-2026-105211?
No fix has been published for CVE-2026-105211 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-105211 being exploited?
There is no known exploitation of CVE-2026-105211 in the wild and no public exploit code.
Sources
Also known as GHSA-3gwm-5wx8-4gm6, GHSA-mq63-7hcv-jfrc.