What is CVE-2026-27898?

CVE-2026-27898 is a medium-severity vulnerability in Dani-garcia Vaultwarden, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 5.4/10. Published 2026-03-04.

How severe is CVE-2026-27898?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Auth bypass in Dani-garcia Vaultwarden

CVE-2026-27898

Vaultwarden is an unofficial Bitwarden compatible server written in Rust, formerly known as bitwarden_rs. Prior to version 1.35.4, an authenticated regular user can specify another user’s cipher_id and call "PUT /api/ciphers/{id}/partial"…

Vulnerability class: IDOR (Insecure Direct Object Reference)

EPSS: 0.000 (12.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

Affected products

Dani-garcia Vaultwarden — versions < 1.35.4

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-w9f8-m526-h7fh (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-27898?: CVE-2026-27898 is a medium-severity vulnerability in Dani-garcia Vaultwarden, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 5.4/10. Published 2026-03-04.
How severe is CVE-2026-27898?: Medium severity. CVSS v3 base score is 5.4 out of 10.