What is CVE-2021-27372?

CVE-2021-27372 is a critical-severity vulnerability in Realtek Xpon Rtl9601d, classified under Insufficiently Protected Credentials. CVSS score: 9.8/10. Published 2021-03-25.

How severe is CVE-2021-27372?

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

Vulnerability in Realtek Xpon Rtl9601d

CVE-2021-27372

Realtek xPON RTL9601D SDK 1.9 stores passwords in plaintext which may allow attackers to possibly gain access to the device with root permissions via the build-in network monitoring tool and execute arbitrary commands.

Published 2021-03-25 · 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: 0.016 (75.4th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 75th percentile — 75.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000

Affected products

Realtek Xpon Rtl9601d
Realtek Xpon Rtl9601d Software Development Kit — versions 1.9

Weakness classification (CWE)

CWE-522 — Insufficiently Protected Credentials

References

www.realtek.com/images/safe-report/RTL9601D_CVE-2021-27372.pdf (Vendor Advisory)

Frequently asked questions

What is CVE-2021-27372?: CVE-2021-27372 is a critical-severity vulnerability in Realtek Xpon Rtl9601d, classified under Insufficiently Protected Credentials. CVSS score: 9.8/10. Published 2021-03-25.
How severe is CVE-2021-27372?: Critical severity. CVSS v3 base score is 9.8 out of 10.