What is CVE-2021-43663?

CVE-2021-43663 is a high-severity vulnerability in Totolink Ex300 V2, classified under Command Injection. CVSS score: 7.5/10. Published 2022-03-31.

How severe is CVE-2021-43663?

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

RCE in Totolink Ex300 V2

CVE-2021-43663

totolink EX300_v2 V4.0.3c.140_B20210429 was discovered to contain a command injection vulnerability via the component cloudupdate_check.

Vulnerability class: Command Injection (OS Command Injection)

Published 2022-03-31 · last modified 2026-06-17.

CVSS v3 metric

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

EPSS exploit prediction

EPSS: 0.010 (59.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 59.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Totolink Ex300 V2
Totolink Ex300 V2 Firmware — versions 4.0.3c.140_b20210429

Weakness classification (CWE)

CWE-77 — Command Injection

References

github.com/chibataiki/iot-vuls/blob/main/totolink/command-injection1.md (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-43663?: CVE-2021-43663 is a high-severity vulnerability in Totolink Ex300 V2, classified under Command Injection. CVSS score: 7.5/10. Published 2022-03-31.
How severe is CVE-2021-43663?: High severity. CVSS v3 base score is 7.5 out of 10.