What is CVE-2021-20159?

CVE-2021-20159 is a high-severity vulnerability in Trendnet Tew-827dru, classified under OS Command Injection. CVSS score: 8.8/10. Published 2021-12-30.

How severe is CVE-2021-20159?

High severity. CVSS v3 base score is 8.8 out of 10.

RCE in Trendnet Tew-827dru

CVE-2021-20159

Trendnet AC2600 TEW-827DRU version 2.08B01 is vulnerable to command injection. The system log functionality of the firmware allows for command injection as root by supplying a malformed parameter.

Vulnerability class: Command Injection (OS Command Injection)

Published 2021-12-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.031 (87.4th percentile), scored 2026-10-07.

Low probability of exploitation in the next 30 days, but still tracked. 87th percentile — 87.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.031 · newest: 0.031 · change: 0.000

Affected products

Trendnet Tew-827dru — versions 2.0
Trendnet Tew-827dru Firmware — versions 2.08b01
Trendnet Ac2600 Tew-827dru — versions 2.08B01

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

www.tenable.com/security/research/tra-2021-54 (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-20159?: CVE-2021-20159 is a high-severity vulnerability in Trendnet Tew-827dru, classified under OS Command Injection. CVSS score: 8.8/10. Published 2021-12-30.
How severe is CVE-2021-20159?: High severity. CVSS v3 base score is 8.8 out of 10.