Ubiquiti UniFi Devices Use of AES-CBC Allows Key Recovery and Unauthorized Device Control

Ubiquiti UniFi Network Controller prior to 5.10.12 (excluding 5.6.42), UAP FW prior to 4.0.6, UAP-AC, UAP-AC v2, and UAP-AC Outdoor FW prior to 3.8.17, USW FW prior to 4.0.6, USG FW prior to 4.4.34 uses AES-CBC encryption for device-to-controller communication, which contains cryptographic weaknesses that allow attackers to recover encryption keys from captured traffic. Attackers with adjacent network access can capture sufficient encrypted traffic and exploit AES-CBC mode vulnerabilities to derive the encryption keys, enabling unauthorized control and management of network devices.