{"cve":"CVE-2022-20653","nvd":{"published":"2022-02-17T15:15:09.377","modified":"2026-06-17T04:24:47.223","status":"Modified","description":"A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient error handling in DNS name resolution by the affected software. An attacker could exploit this vulnerability by sending specially formatted email messages that are processed by an affected device. A successful exploit could allow the attacker to cause the device to become unreachable from management interfaces or to process additional email messages for a period of time until the device recovers, resulting in a DoS condition. Continued attacks could cause the device to become completely unavailable, resulting in a persistent DoS condition.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-399"],"references":["https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-dos-MxZvGtgU","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-dos-MxZvGtgU"],"products":["cisco:asyncos"],"source":"nvd","synced_at":"2026-10-19T21:28:04.509275555+00:00"},"epss":{"cve":"CVE-2022-20653","score":0.01826,"percentile":0.7882,"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."]}