CVE-2026-5102 Totolink A3300R Parameter cstecgi.cgi setSmartQosCfg command injection

Medium 5.3 Published 30 Mar 2026 Updated 30 Mar 2026

Remote attackers can execute arbitrary commands on Totolink A3300R routers via the setSmartQosCfg parameter in cstecgi.cgi.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-5102?

CVE-2026-5102 is a medium-severity command injection vulnerability in Totolink A3300r Firmware, published on 30 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

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.

Weakness: CWE-77, CWE-74

Which versions are affected by CVE-2026-5102?

It affects 1 product.

Products include Totolink A3300r Firmware.

How do I fix CVE-2026-5102?

No fix has been published for CVE-2026-5102 yet. Limit exposure of the affected software until one is available.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2026-5102 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-5102 exists.

All Totolink A3300r Firmware vulnerabilities

Sources

Also known as GHSA-h2wr-p8mq-wj29.