CVE-2026-77556 Denial of service in Cloud Gateways
A remote attacker can cause a denial of service on UniFi network devices via an out-of-bounds read vulnerability.
- 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-2026-77556?
CVE-2026-77556 is a high-severity denial of service vulnerability in Ubiquiti Inc Cloud Gateways, published on 22 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A malicious actor with access to the network could exploit an Out-of-bounds Read vulnerability found in certain UniFi gateway devices to execute a Denial of Service (DoS) attack on the device.
Weakness: CWE-125
Which versions are affected by CVE-2026-77556?
How do I fix CVE-2026-77556?
No fix has been published for CVE-2026-77556 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-77556 being exploited?
There is no known exploitation of CVE-2026-77556 in the wild and no public exploit code.
Sources
Also known as GHSA-rf8m-f7x4-4m54.