{"id":"CVE-2021-22998","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-22998","generatedAt":"2026-10-27T20:22:09.218Z","title":"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, 12.1.x before 12.1.5.3, and 11.6.x before 11.6.5.3, SYN flood protection thresholds are not enforced in secure network address translation…","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, 12.1.x before 12.1.5.3, and 11.6.x before 11.6.5.3, SYN flood protection thresholds are not enforced in secure network address translation (SNAT) listeners. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.","published":"2021-03-31T18:15:15.000Z","lastModified":"2026-06-17T03:38:11.000Z","status":"Modified","sourceIdentifier":"f5sirt@f5.com","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"cwe":[],"affected":["f5/big-ip access policy manager","f5/big-ip advanced firewall manager","f5/big-ip advanced web application firewall","f5/big-ip analytics","f5/big-ip application acceleration manager","f5/big-ip application security manager","f5/big-ip ddos hybrid defender","f5/big-ip domain name system","f5/big-ip fraud protection service","f5/big-ip global traffic manager","f5/big-ip link controller","f5/big-ip local traffic manager","f5/big-ip policy enforcement manager","f5/ssl orchestrator"],"epss":{"score":0.00979,"percentile":0.61961,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.98%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://support.f5.com/csp/article/K31934524","tags":["Vendor Advisory"],"source":"f5sirt@f5.com"},{"url":"https://support.f5.com/csp/article/K31934524","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-22998","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}