RCE in Totolink A8000ru

CVE-2026-9436

A flaw has been found in Totolink A8000RU 7.1cu.643_b20200521. The impacted element is the function setL2tpServerCfg of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. Executing a manipulation of the argument enable can lead to os command injection. The attack can be executed remotely. The exploit has been published and may be used.

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

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: 0.035 (88.6th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 88.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-9436: rose from 0.020 to 0.035.

EPSS over last 30 days · oldest: 0.020 · newest: 0.035 · change: +0.015

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-9436?
CVE-2026-9436 is a critical-severity vulnerability in Totolink A8000ru, classified under Command Injection. CVSS score: 9.8/10. Published 2026-05-25.
How severe is CVE-2026-9436?
Critical severity. CVSS v3 base score is 9.8 out of 10.