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 3.1

9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

0.3% chance of exploitation in the next 30 days; higher than 21% of CVEs (scores of 2026-10-26)

CWE

CWE-307

Published

2026-05-11

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

Affected

• dani-garcia:vaultwarden

References

• https://github.com/dani-garcia/vaultwarden/pull/6867
• https://github.com/dani-garcia/vaultwarden/releases/tag/1.35.4
• https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-c5rv-q295-7w4g
• https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-c5rv-q295-7w4g

Check your stackJSON