What is CVE-2021-34111?

CVE-2021-34111 is a critical-severity vulnerability in Thecus N4800eco, classified under OS Command Injection. CVSS score: 9.8/10. Published 2022-05-20.

How severe is CVE-2021-34111?

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

Is CVE-2021-34111 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

RCE in Thecus N4800eco

CVE-2021-34111

Thecus 4800Eco was discovered to contain a command injection vulnerability via the username parameter in /adm/setmain.php.

Vulnerability class: Command Injection (OS Command Injection)

Published 2022-05-20 · 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: 0.027 (85.2th percentile), scored 2026-10-07.

Low probability of exploitation in the next 30 days, but still tracked. 85th percentile — 85.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.027 · newest: 0.027 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-78 — OS Command Injection

Public proof-of-concept exploits

ARPSyndicate/cve-scores

References

docs.unsafe-inline.com/0day/thecus-n4800eco-nas-server-control-panel-comand-inj… (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-34111?: CVE-2021-34111 is a critical-severity vulnerability in Thecus N4800eco, classified under OS Command Injection. CVSS score: 9.8/10. Published 2022-05-20.
How severe is CVE-2021-34111?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2021-34111 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.