Critical F5 BIG-IP flaw allows device takeover, patch ASAP! (CVE-2022-1388)

F5 BIG-IP and BIG-IQ Centralized Management contain a remote code execution vulnerability (CWE-863, improper authorization check) in the iControl REST interface. An unauthenticated attacker with network access to the REST endpoint can send crafted requests to execute arbitrary system commands, create or delete files, and disable services on the appliance or virtual instance. Successful exploitation effectively gives the attacker command-level control of the underlying F5 system, which is sufficient for account creation, persistence, lateral movement, and ransomware staging. Any organization running affected BIG-IP or BIG-IQ releases is exposed, particularly where the management interface or iControl REST is reachable from untrusted networks. Exploitation is confirmed in the wild: the flaw was added to CISA's KEV on 2021-11-03 with known ransomware use, EPSS places the 30-day exploitation probability at 99.9% (top percentile), though no public PoC is cataloged.

Do: Upgrade BIG-IP and BIG-IQ to the fixed releases identified in F5's advisory (K03051234) on an urgent basis, since exploitation is in the wild and ransomware actors use this flaw. Until patched, restrict network access to the management interface and iControl REST to trusted administration networks. Because ransomware use is known, review affected devices for indicators of compromise such as unexpected commands, created or deleted files, and disabled services.

F5 BIG-IP contains a critical missing-authentication flaw (CWE-306) in its iControl REST control plane: an unauthenticated attacker with network reachability to the management interface, or to self IPs exposing the REST service on TCP 443, can bypass authentication completely. By sending specially crafted HTTP requests, the attacker gains the ability to execute arbitrary code, create or delete files, and disable services, effectively achieving full takeover of the load balancer or security appliance and the traffic it handles. All F5 BIG-IP deployments running unpatched software are affected; the provided data does not enumerate exact version ranges, which are listed in F5's May 2022 security advisory. The flaw was added to CISA's KEV catalog on 2022-05-10 with known ransomware use, and EPSS assigns a 100% probability of exploitation within 30 days (100th percentile), indicating active in-the-wild exploitation. No public proof-of-concept is catalogued in the provided data, but the KEV listing and known ransomware use confirm real-world attacks.

Do: Upgrade affected F5 BIG-IP systems to the fixed releases listed in F5's May 2022 security advisory (K23605340) immediately, prioritizing appliances whose management interface or self IPs on TCP 443 are reachable from untrusted networks; as an interim mitigation, block untrusted access to the management interface and the iControl REST service. Because this flaw is in CISA's KEV catalog with known ransomware use, also hunt for signs of compromise (unexpected files, disabled services, unknown persistence) on any system that was exposed before patching.