{"cve":"CVE-2023-20081","nvd":{"published":"2023-03-23T17:15:14.873","modified":"2026-08-11T19:33:44.513","status":"Modified","description":"A vulnerability in the IPv6 DHCP (DHCPv6) client module of Cisco Adaptive Security Appliance (ASA) Software, Cisco Firepower Threat Defense (FTD) Software, Cisco IOS Software, and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of DHCPv6 messages. An attacker could exploit this vulnerability by sending crafted DHCPv6 messages to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. Note: To successfully exploit this vulnerability, the attacker would need to either control the DHCPv6 server or be in a man-in-the-middle position.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.9},"cwes":["CWE-787","CWE-122"],"references":["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftdios-dhcpv6-cli-Zf3zTv","https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftdios-dhcpv6-cli-Zf3zTv"],"products":["cisco:adaptive_security_appliance_software","cisco:ios","cisco:ios_xe","cisco:secure_firewall_threat_defense"],"source":"nvd","synced_at":"2026-10-19T21:37:48.383111019+00:00"},"epss":{"cve":"CVE-2023-20081","score":0.00678,"percentile":0.52334,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}