CVE-2026-51742 Missing authorization in n/a

Medium 5.9 Published Updated

Unauthenticated attackers can trigger WAN discovery logic on TOTOLINK T6 routers via a crafted POST request due to incorrect access control.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Over the internet
Victim action needed
Not needed
Fix
None listed

What is CVE-2026-51742?

CVE-2026-51742 is a medium-severity missing authorization vulnerability in n/a, published on 1 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Incorrect access control in the discoverWan function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to trigger WAN discovery logic via sending a crafted POST request to /cgi-bin/cstecgi.cgi.

Weakness: CWE-284

Which versions are affected by CVE-2026-51742?

How do I fix CVE-2026-51742?

No fix has been published for CVE-2026-51742 yet. Limit exposure of the affected software until one is available.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2026-51742 being exploited?

There is no known exploitation of CVE-2026-51742 in the wild and no public exploit code.

Sources

Also known as GHSA-fhqw-9mv9-g6cr.

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