What is CVE-2021-35941?

CVE-2021-35941 is a high-severity vulnerability in Westerndigital Wd My Book Live, classified under Missing Authentication for Critical Function. CVSS score: 7.5/10. Published 2021-06-29.

How severe is CVE-2021-35941?

High severity. CVSS v3 base score is 7.5 out of 10.

Auth bypass in Westerndigital Wd My Book Live

CVE-2021-35941

Western Digital WD My Book Live (2.x and later) and WD My Book Live Duo (all versions) have an administrator API that can perform a system factory restore without authentication, as exploited in the wild in June 2021, a different vulnerability than CVE-2018-18472.

Vulnerability class: Broken Authentication

Published 2021-06-29 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.127 (96.2th percentile), scored 2026-10-07.

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 96th percentile — 96.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.127 · newest: 0.127 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

References

www.westerndigital.com/support/productsecurity/wdc-21008-recommended-security-m… (Vendor Advisory)
arstechnica.com/gadgets/2021/06/hackers-exploited-0-day-not-2018-bug-to-mass-wi… (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-35941?: CVE-2021-35941 is a high-severity vulnerability in Westerndigital Wd My Book Live, classified under Missing Authentication for Critical Function. CVSS score: 7.5/10. Published 2021-06-29.
How severe is CVE-2021-35941?: High severity. CVSS v3 base score is 7.5 out of 10.