What is CVE-2020-12830?

CVE-2020-12830 is a critical-severity vulnerability in Westerndigital My Cloud Ex4100, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2020-10-27.

How severe is CVE-2020-12830?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Westerndigital My Cloud Ex4100

CVE-2020-12830

Addressed multiple stack buffer overflow vulnerabilities that could allow an attacker to carry out escalation of privileges through unauthorized remote code execution in Western Digital My Cloud devices before 5.04.114.

Vulnerability class: Buffer Overflow

Published 2020-10-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.033 (88.2th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 88th percentile — 88.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.033 · newest: 0.033 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

support.wdc.com/downloads.aspx (Vendor Advisory)
www.westerndigital.com/support/productsecurity/wdc-20007-my-cloud-firmware-vers… (Vendor Advisory)

Frequently asked questions

What is CVE-2020-12830?: CVE-2020-12830 is a critical-severity vulnerability in Westerndigital My Cloud Ex4100, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2020-10-27.
How severe is CVE-2020-12830?: Critical severity. CVSS v3 base score is 9.8 out of 10.