A malicious actor who has connected to a Ubiquiti network and possesses a low‑privilege account can exploit an improper access control flaw in certain UniFi OS devices. The weakness, identified as CWE‑284, allows the attacker to elevate their privileges beyond the intended level, enabling configuration changes, network service disruption, or a persistent foothold for further attacks.

The vulnerability affects a broad spectrum of Ubiquiti hardware running UniFi OS, including Cloud Gateways, Cloud Keys, Dream Machines, Dream Routers, Dream Wall, Enterprise Firewall Core, Enterprise Fortress Gateway, Enterprise NVRs, Express 7, Network Attached Storage, Network Video Recorders, and the UniFi OS Server. No specific firmware version numbers are provided, so any device in the list should be checked against the latest firmware releases for the fix.

With a CVSS score of 9.9 this issue is classified as critical. The EPSS score is not available, and the vulnerability is not listed in the CISA KEV catalog. Nevertheless, the attack requires only internal network access and low‑privilege credentials, which are commonly available to users or remote attackers on the same LAN. The combination of a severe impact and simple attack prerequisites results in a substantial risk for any organization that hosts these devices.