CVE-2026-77555 Memory corruption in Cloud Gateways
A remote attacker can cause a denial of service on UniFi network devices via an out-of-bounds write 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-2026-77555?
CVE-2026-77555 is a high-severity memory corruption 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 Write vulnerability found in certain UniFi gateway devices to execute a Denial of Service (DoS) attack on the device.
Weakness: CWE-787
Which versions are affected by CVE-2026-77555?
How do I fix CVE-2026-77555?
No fix has been published for CVE-2026-77555 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-77555 being exploited?
There is no known exploitation of CVE-2026-77555 in the wild and no public exploit code.
Sources
Also known as GHSA-gx3q-h4jp-wj72.