{"schema_version":"public-product-v1.1","generated_at":"2026-07-21T11:05:14Z","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","advisory":{"id":"cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","slug":"cisco-sa-ftd-tls-decrypt-dos-bmxyjm8m","vendor":"Cisco","title":"Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Software-Based SSL/TLS Denial of Service Vulnerability","summary":"A vulnerability in the software-based SSL/TLS message handler of Cisco&nbsp;Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient validation of SSL/TLS messages when the device performs software-based SSL/TLS decryption. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: Datagram TLS (DTLS) messages cannot be used to exploit this vulnerability. Cisco&nbsp;has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M This advisory is part of the October 2021 release of the Cisco&nbsp;ASA, FTD, and FMC Security Advisory Bundled publication. For a complete list of the advisories and links to them, see Cisco&nbsp;Event Response: October 2021 Cisco&nbsp;ASA, FMC, and FTD Software Security Advisory Bundled Publication.","severity":"High","published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","csaf_url":"https://sec.cloudapps.cisco.com/security/center/contentjson/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M/csaf/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M.json","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure."},"freshness":{"last_source_refreshed_at":"2026-07-21T05:16:34Z","latest_source_refresh_at":"2026-07-21T05:16:34Z","oldest_source_refresh_at":"2026-07-21T03:00:03Z","all_sources_fresh":true,"sources":[{"source":"cisco_advisories","label":"Cisco advisories","last_success_at":"2026-07-21T03:00:03Z","stale":false},{"source":"cisco_csaf","label":"Cisco CSAF","last_success_at":"2026-07-21T05:14:24Z","stale":false},{"source":"nvd_cves","label":"NVD CVEs","last_success_at":"2026-07-21T05:16:30Z","stale":false},{"source":"cisa_kev","label":"CISA KEV","last_success_at":"2026-07-21T05:16:31Z","stale":false},{"source":"first_epss","label":"EPSS","last_success_at":"2026-07-21T05:16:34Z","stale":false}]},"summary":{"cve_count":1,"visible_product_count":8,"public_evidence_count":8,"kev_count":0,"highest_epss":0.0155},"cves":[{"id":"CVE-2021-34783","kev":false,"epss":{"score":0.0155,"percentile":0.72352,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"}}],"public_evidence":[{"product":{"name":"Cisco Firepower 2100 Series","slug":"cisco-firepower-2100-series","vendor":"Cisco"},"cve":{"id":"CVE-2021-34783"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T04:46:13Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.1 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.10 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.11 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.12 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.3 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.4 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.5 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.6 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.7 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.8 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.9 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.1 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.3 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.4 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1 when installed on Cisco Firepower 2100 Series","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.0155,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","advisory_updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M"},"row_display_order":1},{"product":{"name":"Cisco Firepower 1000 Series","slug":"cisco-firepower-1000-series","vendor":"Cisco"},"cve":{"id":"CVE-2021-34783"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T04:46:13Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.10 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.11 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.12 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.3 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.4 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.5 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.6 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.7 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.8 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.9 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.1 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.3 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.4 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1 when installed on Cisco Firepower 1000 Series","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.0155,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","advisory_updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M"},"row_display_order":2},{"product":{"name":"Cisco ASA 5500-X Series Firewalls","slug":"cisco-asa-5500-x-series-firewalls","vendor":"Cisco"},"cve":{"id":"CVE-2021-34783"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T04:46:13Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.1 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.10 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.11 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.12 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.3 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.4 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.5 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.6 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.7 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.8 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.9 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.1 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.3 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.4 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1 when installed on Cisco ASA 5500-X Series Firewalls","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.0155,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","advisory_updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M"},"row_display_order":3},{"product":{"name":"Cisco 3000 Series Industrial Security Appliances (ISA)","slug":"cisco-3000-series-industrial-security-appliances-isa","vendor":"Cisco"},"cve":{"id":"CVE-2021-34783"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T04:46:13Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.10 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.11 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.12 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.3 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.4 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.5 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.6 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.7 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.8 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.9 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.6.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.6.3 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 6.6.4 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.0155,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","advisory_updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M"},"row_display_order":4},{"product":{"name":"Cisco Firepower 9000 Series","slug":"cisco-firepower-9000-series","vendor":"Cisco"},"cve":{"id":"CVE-2021-34783"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T04:46:13Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.1 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.10 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.11 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.12 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.3 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.4 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.5 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.6 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.7 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.8 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.9 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.1 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.3 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.4 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1 when installed on Cisco Firepower 9000 Series","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.0155,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","advisory_updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M"},"row_display_order":5},{"product":{"name":"Cisco Firepower 4100 Series","slug":"cisco-firepower-4100-series","vendor":"Cisco"},"cve":{"id":"CVE-2021-34783"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T04:46:13Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.1 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.10 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.11 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.12 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.3 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.4 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.5 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.6 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.7 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.8 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.9 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.1 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.3 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.4 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1 when installed on Cisco Firepower 4100 Series","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.0155,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","advisory_updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M"},"row_display_order":6},{"product":{"name":"Cisco Adaptive Security Virtual Appliance (ASAv)","slug":"cisco-adaptive-security-virtual-appliance-asav","vendor":"Cisco"},"cve":{"id":"CVE-2021-34783"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T04:46:13Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Adaptive Security Virtual Appliance (ASAv)","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.0155,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","advisory_updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M"},"row_display_order":7},{"product":{"name":"Cisco Secure Firewall Threat Defense Virtual","slug":"cisco-secure-firewall-threat-defense-virtual","vendor":"Cisco"},"cve":{"id":"CVE-2021-34783"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T04:46:13Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.1 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.10 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.11 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.12 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.3 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.4 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.5 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.6 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.7 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.8 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.4.0.9 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.1 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.3 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 6.6.4 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 when installed on Cisco Secure Firewall Threat Defense Virtual; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1 when installed on Cisco Secure Firewall Threat Defense Virtual","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.0155,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2021-10-27T16:00:00Z","updated_at":"2021-10-27T16:00:00Z","advisory_updated_at":"2021-10-27T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8M"},"row_display_order":8}]}