{"schema":"threatline.record/2","record":{"id":"CVE-2021-22991","aliases":[],"summary":"F5 BIG-IP Traffic Management Microkernel Buffer Overflow","details":"The Traffic Management Microkernel of BIG-IP ASM Risk Engine has a buffer overflow vulnerability, leading to a bypassing of URL-based access controls.","categories":["Network & edge"],"product":"BIG-IP Traffic Management Microkernel","vendor":"F5","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2021-22991","source_modified_at":"2025-10-21T23:25:50.646Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"BIG-IP","vendor":"n/a","versions":[{"status":"affected","version":"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, 12.1.x before 12.1.5.3"}],"defaultStatus":null}],"fixed_versions":[],"cvss":9.8,"severity":"Critical","kev":{"listed":true,"date_added":"2022-01-18","due_date":"2022-02-01","required_action":"Apply updates per vendor instructions.","ransomware_campaign_use":"Unknown"},"epss":{"probability":0.61064,"percentile":0.9916,"score_date":"2026-10-23"},"published_at":"2021-03-31T17:23:14.000Z","modified_at":"2025-10-21T23:25:50.646Z","provenance":[{"source":"CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T17:00:09.9001Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2021-22991","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2025-10-21T23:25:50.646Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2021-22991","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CISA KEV","CVE List","EPSS"],"references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-22991","source":"CISA KEV"},{"source":"CVE List","url":"https://support.f5.com/csp/article/K56715231","tags":["x_refsource_MISC","x_transferred"]},{"source":"CVE List","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-22991","tags":["government-resource"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CISA ADP","ssvc":{"exploitation":"active","automatable":"yes","technical_impact":"total","assessed_at":"2025-01-29T20:33:09.572716Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2025-10-21T23:25:50.646Z","content_hash":"550c25efb67f3084101d61dd841231d9fd59c922f8407032c25206b410f3a2e4"}}