CVE-2026-43914

criticalpriority · attend · 49EPSS 0.003 · 21 %ileexploit · PoCDEEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

0.29% (21st) EPSS

CVSS 9.8 · critical

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.3–9.8

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.17.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · ENISA EU

v3.17.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · security-advisories@github.comexploitability 3.9 · impact 3.4

v3.19.3criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Psecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-307US

exploits (1)

Public proof-of-concept and weaponised exploit code.

Boreas37/CVE-2026-43914-PoCPoC for CVE-2026-43914: Vaultwarden <1.35.4 email-2FA brute-force bypass password oracle. Stdlib-only Python.PoC · poc_in_github

affected products (4)

Products and version ranges known to be affected.

Open Source Vaultwarden <1.35.5all versionscert_bundDE
Open Source Vaultwarden< 1.35.5cert_bundDE
dani-garcia vaultwarden≤ < 1.35.4enisa_euvdEU
dani-garcia vaultwarden< 1.35.4nvdUScpe:2.3:a:dani-garcia:vaultwarden:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-1285Vaultwarden: Mehrere SchwachstellenDeutsch2026-04-26csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Vaultwarden ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, und um Informationen offenzulegen.

also known as (2)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2026-05-11modified 2026-10-26

references (8)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan