CVE-2026-43914

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.

CVSS v3 7.3 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/dani-garcia/vaultwarden/pull/6867	Issue Tracking Patch
https://github.com/dani-garcia/vaultwarden/releases/tag/1.35.4	Product Release Notes
https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-c5rv-q295-7w4g	Exploit Patch Vendor Advisory
https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-c5rv-q295-7w4g	Exploit Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:dani-garcia:vaultwarden:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-11 23:20

Updated : 2026-06-17 10:50

NVD link : CVE-2026-43914

Mitre link : CVE-2026-43914

CVE.ORG link : CVE-2026-43914

JSON object : View

Products Affected

dani-garcia

vaultwarden

CWE

CWE-307

Improper Restriction of Excessive Authentication Attempts

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