F5 BIG-IP appliances 9.x before 9.4.8-HF5, 10.x before 10.2.4, 11.0.x before 11.0.0-HF2, and 11.1.x before 11.1.0-HF3, and Enterprise Manager before 2.1.0-HF2, 2.2.x before 2.2.0-HF1, and 2.3.x before 2.3.0-HF3, use a single SSH private key across different customers' installations and do not properly restrict access to this key, which makes it easier for remote attackers to perform SSH logins via the PubkeyAuthentication option.