CVE-2026-51756 Missing authorization in n/a
Unauthenticated attackers can trigger firmware flashing via crafted MQTT messages, potentially leading to code execution or privilege escalation on TOTOLINK T6 devices.
- 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-2026-51756?
CVE-2026-51756 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 meshSlaveUpgfw function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to start firmware flashing using existing upgrade files via sending a crafted MQTT message to the cs_broker component.
Weakness: CWE-284
Which versions are affected by CVE-2026-51756?
How do I fix CVE-2026-51756?
No fix has been published for CVE-2026-51756 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-2026-51756 being exploited?
There is no known exploitation of CVE-2026-51756 in the wild and no public exploit code.
Sources
Also known as GHSA-53c4-935x-4h8m.