{"id":"CVE-2026-20006","state":"PUBLISHED","title":"Cisco Firepower Threat Defense Software and Cisco FirePOWER Services TLS with Snort 3 Denial of Service Vulnerability","description":"A vulnerability in the TLS cryptography functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to unexpectedly restart, resulting in a denial of service (DoS) condition.\r\n\r\nThis vulnerability is due to improper implementation of the TLS protocol. An attacker could exploit this vulnerability by sending a crafted TLS packet to an affected system. A successful exploit could allow the attacker to cause a device that is running Cisco Secure FTD Software to drop network traffic, resulting in a DoS condition. \r\nNote: TLS 1.3 is not affected by this vulnerability.","publishedAt":"2026-03-04T17:37:54.866Z","updatedAt":"2026-03-04T20:51:58.937Z","severity":{"score":5.8,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L","source":"cisco"},"assigner":"cisco","products":["Cisco Cisco Secure Firewall Threat Defense (FTD) Software"],"affected":[{"vendor":"Cisco","product":"Cisco Secure Firewall Threat Defense (FTD) Software","defaultStatus":"unknown","versions":[{"version":"7.2.0","status":"affected"},{"version":"7.2.0.1","status":"affected"},{"version":"7.2.1","status":"affected"},{"version":"7.3.0","status":"affected"},{"version":"7.2.2","status":"affected"},{"version":"7.2.3","status":"affected"},{"version":"7.3.1","status":"affected"},{"version":"7.2.4","status":"affected"},{"version":"7.2.5","status":"affected"},{"version":"7.2.4.1","status":"affected"},{"version":"7.3.1.1","status":"affected"},{"version":"7.4.0","status":"affected"},{"version":"7.2.5.1","status":"affected"},{"version":"7.4.1","status":"affected"},{"version":"7.2.6","status":"affected"},{"version":"7.4.1.1","status":"affected"},{"version":"7.2.7","status":"affected"},{"version":"7.2.5.2","status":"affected"},{"version":"7.3.1.2","status":"affected"},{"version":"7.2.8","status":"affected"},{"version":"7.6.0","status":"affected"},{"version":"7.4.2","status":"affected"},{"version":"7.2.8.1","status":"affected"},{"version":"7.4.2.1","status":"affected"},{"version":"7.2.9","status":"affected"},{"version":"7.4.2.2","status":"affected"},{"version":"7.2.10","status":"affected"},{"version":"7.6.1","status":"affected"},{"version":"7.4.2.3","status":"affected"},{"version":"7.6.2","status":"affected"},{"version":"7.6.2.1","status":"affected"},{"version":"7.4.2.4","status":"affected"},{"version":"7.2.10.2","status":"affected"}]}],"references":["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tcp-dos-rHfqnwRg"],"weaknesses":["CWE-388"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/20xxx/CVE-2026-20006.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-20006","state":"PUBLISHED","datePublished":"2026-03-04T17:37:54.866Z","dateUpdated":"2026-03-04T20:51:58.937Z","assignerShortName":"cisco","assignerOrgId":"d1c1063e-7a18-46af-9102-31f8928bc633","dateReserved":"2025-10-08T11:59:15.349Z"},"containers":{"cna":{"title":"Cisco Firepower Threat Defense Software and Cisco FirePOWER Services TLS with Snort 3 Denial of Service Vulnerability","descriptions":[{"lang":"en","value":"A vulnerability in the TLS cryptography functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to unexpectedly restart, resulting in a denial of service (DoS) condition.\r\n\r\nThis vulnerability is due to improper implementation of the TLS protocol. An attacker could exploit this vulnerability by sending a crafted TLS packet to an affected system. A successful exploit could allow the attacker to cause a device that is running Cisco Secure FTD Software to drop network traffic, resulting in a DoS condition. \r\nNote: TLS 1.3 is not affected by this vulnerability."}],"affected":[{"vendor":"Cisco","product":"Cisco Secure Firewall Threat Defense (FTD) Software","defaultStatus":"unknown","versions":[{"version":"7.2.0","status":"affected"},{"version":"7.2.0.1","status":"affected"},{"version":"7.2.1","status":"affected"},{"version":"7.3.0","status":"affected"},{"version":"7.2.2","status":"affected"},{"version":"7.2.3","status":"affected"},{"version":"7.3.1","status":"affected"},{"version":"7.2.4","status":"affected"},{"version":"7.2.5","status":"affected"},{"version":"7.2.4.1","status":"affected"},{"version":"7.3.1.1","status":"affected"},{"version":"7.4.0","status":"affected"},{"version":"7.2.5.1","status":"affected"},{"version":"7.4.1","status":"affected"},{"version":"7.2.6","status":"affected"},{"version":"7.4.1.1","status":"affected"},{"version":"7.2.7","status":"affected"},{"version":"7.2.5.2","status":"affected"},{"version":"7.3.1.2","status":"affected"},{"version":"7.2.8","status":"affected"},{"version":"7.6.0","status":"affected"},{"version":"7.4.2","status":"affected"},{"version":"7.2.8.1","status":"affected"},{"version":"7.4.2.1","status":"affected"},{"version":"7.2.9","status":"affected"},{"version":"7.4.2.2","status":"affected"},{"version":"7.2.10","status":"affected"},{"version":"7.6.1","status":"affected"},{"version":"7.4.2.3","status":"affected"},{"version":"7.6.2","status":"affected"},{"version":"7.6.2.1","status":"affected"},{"version":"7.4.2.4","status":"affected"},{"version":"7.2.10.2","status":"affected"}]}],"references":[{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tcp-dos-rHfqnwRg","name":"cisco-sa-ftd-tcp-dos-rHfqnwRg"}],"metrics":[{"format":"cvssV3_1","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L","baseScore":5.8,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"LOW"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-388","lang":"en","description":"Error Handling","type":"cwe"}]}],"providerMetadata":{"shortName":"cisco","orgId":"d1c1063e-7a18-46af-9102-31f8928bc633","dateUpdated":"2026-03-04T17:37:54.866Z"},"exploits":[{"lang":"en","value":"The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory."}],"source":{"advisory":"cisco-sa-ftd-tcp-dos-rHfqnwRg","discovery":"INTERNAL","defects":["CSCwn73801"]}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-03-04T20:51:52.748707Z","id":"CVE-2026-20006","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-03-04T20:51:58.937Z"}}]}}}