CVE-2026-51639 Missing authorization in n/a

Medium 4.3 Published Updated

Unauthenticated attackers can obtain Wi-Fi scheduling rules from TOTOLINK T6 routers via a crafted POST request due to incorrect access control.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Local or same network only
Victim action needed
Not needed
Fix
None listed

What is CVE-2026-51639?

CVE-2026-51639 is a medium-severity missing authorization vulnerability in n/a, published on 28 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Incorrect access control in the getApWiFiSchCfg function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to obtain AP-specific Wi-Fi scheduling rules via sending a crafted POST request to /cgi-bin/cstecgi.cgi.

Weakness: CWE-284

Which versions are affected by CVE-2026-51639?

How do I fix CVE-2026-51639?

No fix has been published for CVE-2026-51639 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-2026-51639 being exploited?

There is no known exploitation of CVE-2026-51639 in the wild and no public exploit code.

Sources

Also known as GHSA-r23g-55x5-xvm5.

Is CVE-2026-51639 in your software?

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