CVE-2026-43914 (GCVE-0-2026-43914)

Vulnerability from cvelistv5 – Published: 2026-05-11 22:03 – Updated: 2026-05-12 12:51
VLAI
Title
Vaultwarden: Brute-force protection bypass vulnerability
Summary
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.
Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-12 12:51 UTC
CWE
  • CWE-307 - Improper Restriction of Excessive Authentication Attempts
Assigner
References
Impacted products
Vendor Product Version CPE status
dani-garcia vaultwarden Affected: < 1.35.4
guessed Create a notification for this product.
Show details on NVD website
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