Description
A vulnerability in the EnableTwoFactorAuthRequest SOAP endpoint of Zimbra Collaboration (ZCS) allows an attacker with valid user credentials to bypass Two-Factor Authentication (2FA) protection. The attacker can configure an additional 2FA method (either a third-party authenticator app or email-based 2FA) without presenting a valid authentication token or proving access to an already configured 2FA method. This bypasses 2FA and results in unauthorized access to accounts that are otherwise protected by 2FA.
References3
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 1% percentile: 51 · as of 8 November 2026
- CWE
- CWE-284
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