RCE in Totolink A3300r

CVE-2026-5102

A security flaw has been discovered in Totolink A3300R 17.0.0cu.557_b20221024. This vulnerability affects the function setSmartQosCfg of the file /cgi-bin/cstecgi.cgi of the component Parameter Handler. The manipulation of the argument qos_up_bw results in command injection. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.

EPSS exploit prediction

EPSS: 0.035 (88.9th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 88.9% 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-2026-5102: rose from 0.024 to 0.035.

EPSS over last 30 days · oldest: 0.024 · newest: 0.035 · change: +0.012

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-5102?
CVE-2026-5102 is a medium-severity vulnerability in Totolink A3300r, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 6.3/10. Published 2026-03-30.
How severe is CVE-2026-5102?
Medium severity. CVSS v3 base score is 6.3 out of 10.