{"id":"CVE-2020-3306","title":"A vulnerability in the DHCP module of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the …","summary":"A vulnerability in the DHCP module of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the …","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-400","CWE-400"],"vendor":"cisco","product":"adaptive_security_appliance","affected":["adaptive_security_appliance < 9.6.4.34","adaptive_security_appliance_software >= 9.7, < 9.8.4.10","adaptive_security_appliance_software >= 9.9, < 9.10.1.30","adaptive_security_appliance_software >= 9.12, < 9.12.3","secure_firewall_threat_defense < 6.3.0.5","secure_firewall_threat_defense >= 6.4.0, < 6.4.0.4"],"patched":["adaptive_security_appliance 9.6.4.34","adaptive_security_appliance_software 9.12.3","secure_firewall_threat_defense 6.4.0.4"],"published":"2020-05-06","updated":"2026-08-11","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2020-3306","references":[{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-dos-qk8cTGLz","label":"psirt@cisco.com"},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-dos-qk8cTGLz","label":"af854a3a-2127-422b-91ae-364da2661108"}],"tags":["nvd"],"epss":0.01233,"epssPercentile":0.672,"ingestedAt":"2026-08-11T19:48:28.148Z","slug":"CVE-2020-3306","body":"## Overview\n\nA vulnerability in the DHCP module of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability is due to incorrect processing of certain DHCP packets. An attacker could exploit this vulnerability by sending a crafted DHCP packet to the affected device. A successful exploit could allow the attacker to cause a DoS condition on the affected device.\n\n## Affected\n\n- `adaptive_security_appliance < 9.6.4.34`\n- `adaptive_security_appliance_software >= 9.7, < 9.8.4.10`\n- `adaptive_security_appliance_software >= 9.9, < 9.10.1.30`\n- `adaptive_security_appliance_software >= 9.12, < 9.12.3`\n- `secure_firewall_threat_defense < 6.3.0.5`\n- `secure_firewall_threat_defense >= 6.4.0, < 6.4.0.4`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `adaptive_security_appliance 9.6.4.34`\n- `adaptive_security_appliance_software 9.12.3`\n- `secure_firewall_threat_defense 6.4.0.4`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}