{"cve_id":"CVE-2021-22991","published":"2021-03-31T18:15:14.787000+00:00","last_modified":"2026-06-17T03:38:10.083000+00:00","vuln_status":"Analyzed","description":"On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, and 12.1.x before 12.1.5.3, undisclosed requests to a virtual server may be incorrectly handled by the Traffic Management Microkernel (TMM) URI normalization, which may trigger a buffer overflow, resulting in a DoS attack. In certain situations, it may theoretically allow bypass of URL based access control or remote code execution (RCE). Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.","cvss_version":"3.1","cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","base_score":9.8,"base_severity":"CRITICAL","attack_vector":"NETWORK","privileges_req":"NONE","user_interaction":"NONE","scope":"UNCHANGED","impact_c":"HIGH","impact_i":"HIGH","impact_a":"HIGH","cwe_ids":["CWE-119"],"in_kev":true,"kev_date_added":"2022-01-18","kev_ransomware":false,"epss_score":0.62421,"epss_percentile":0.99186,"cap_rule_version":"0.1.1","stage":"INITIAL_ACCESS","req_access":"NONE","req_vector":"NETWORK","req_user_interaction":false,"grant_access":"USER","caps":["CODE_EXEC"],"terminal":false,"cap_confidence":"high","ingested_at":"2026-09-18T09:37:49.285398+00:00","first_seen":"2021-03-31T18:15:14.787000+00:00","kev_first_seen":"2022-01-18T00:00:00+00:00","novelty_score":0.0,"novelty_reasons":[],"novelty_at":null,"vendors":["f5"],"products":["big-ip_access_policy_manager","big-ip_advanced_firewall_manager","big-ip_advanced_web_application_firewall","big-ip_analytics","big-ip_application_acceleration_manager","big-ip_application_security_manager","big-ip_ddos_hybrid_defender","big-ip_domain_name_system","big-ip_fraud_protection_service","big-ip_global_traffic_manager","big-ip_link_controller","big-ip_local_traffic_manager","big-ip_policy_enforcement_manager","ssl_orchestrator"],"affected":[{"vendor":"f5","product":"big-ip_access_policy_manager","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_advanced_firewall_manager","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_advanced_web_application_firewall","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_analytics","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_application_acceleration_manager","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_application_security_manager","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_ddos_hybrid_defender","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_domain_name_system","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_fraud_protection_service","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_global_traffic_manager","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_link_controller","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_local_traffic_manager","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"big-ip_policy_enforcement_manager","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]},{"vendor":"f5","product":"ssl_orchestrator","ranges":["≥ 12.1.0 and < 12.1.5.3","≥ 13.1.0 and < 13.1.3.6","≥ 14.1.0 and < 14.1.4","≥ 15.1.0 and < 15.1.2.1","≥ 16.0.0 and < 16.0.1.1"]}]}