{"cve":"CVE-2023-20083","nvd":{"published":"2023-11-01T18:15:09.143","modified":"2026-08-11T19:33:44.513","status":"Modified","description":"A vulnerability in ICMPv6 inspection when configured with the Snort 2 detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the CPU of an affected device to spike to 100 percent, which could stop all traffic processing and result in a denial of service (DoS) condition. FTD management traffic is not affected by this vulnerability. This vulnerability is due to improper error checking when parsing fields within the ICMPv6 header. An attacker could exploit this vulnerability by sending a crafted ICMPv6 packet through an affected device. A successful exploit could allow the attacker to cause the device to exhaust CPU resources and stop processing traffic, resulting in a DoS condition. Note: To recover from the DoS condition, the Snort 2 Detection Engine or the Cisco FTD device may need to be restarted.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","score":8.6},"cwes":["CWE-835"],"references":["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-icmpv6-dos-4eMkLuN","https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-icmpv6-dos-4eMkLuN"],"products":["cisco:secure_firewall_threat_defense"],"source":"nvd","synced_at":"2026-10-19T21:40:11.519948003+00:00"},"epss":{"cve":"CVE-2023-20083","score":0.00699,"percentile":0.53136,"date":"2026-10-31"},"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."]}