What is CVE-2026-31177?

CVE-2026-31177 is a critical-severity vulnerability in Totolink A3300r, classified under OS Command Injection. CVSS score: 9.8/10. Published 2026-04-23.

How severe is CVE-2026-31177?

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

RCE in Totolink A3300r

CVE-2026-31177

An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary commands via the stunMinAlive parameter to /cgi-bin/cstecgi.cgi.

Vulnerability class: Command Injection (OS Command Injection)

Published 2026-04-23 · 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: 0.014 (72.3th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 72nd percentile — 72.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.014 · change: +0.009

Affected products

Totolink A3300r
Totolink A3300r Firmware — versions 17.0.0cu.557_b20221024

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

github.com/Svigo-o/TOTOLINK-Vul/tree/main/totolink-a3300r-stun-min-alive-cmd-in… (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2026-31177?: CVE-2026-31177 is a critical-severity vulnerability in Totolink A3300r, classified under OS Command Injection. CVSS score: 9.8/10. Published 2026-04-23.
How severe is CVE-2026-31177?: Critical severity. CVSS v3 base score is 9.8 out of 10.