CVE-2026-43914
Vaultwarden: Brute-force protection bypass vulnerability
- State
- Published
- Severity
- 7.3 High
- Published
- May 11, 2026
- Updated
- May 12, 2026
- Reserved
- May 4, 2026
Description
Vaultwarden is a Bitwarden-compatible server written in Rust. Prior to 1.35.4, there is a security vulnerability in Vaultwarden that allows bypassing the login brute-force protection if email 2fa is enabled. If email 2fa is enabled, the unprotected 2fa-function send_email_login (email.rs, api endpoint /api/two-factor/send-email-login) also acts as an oracle determining whether a username-password combination is correct. An attacker can abuse that endpoint to brute-force passwords without rate-limiting. This works even for users who don't have email 2fa configured. This vulnerability is fixed in 1.35.4.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.3 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L | GitHub_M |
Weaknesses
- CWE-307 Improper Restriction of Excessive Authentication Attempts
Affected Products
| Product | Versions |
|---|---|
vaultwardendani-garcia |
|
References
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