{"cve":"CVE-2019-1831","nvd":{"published":"2019-04-18T02:29:05.747","modified":"2026-06-17T02:29:24.617","status":"Modified","description":"A vulnerability in the email message scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured content filters on the device. The vulnerability is due to improper input validation of the email body. An attacker could exploit this vulnerability by inserting specific character strings in the message. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","score":5.3},"cwes":["CWE-20"],"references":["http://www.securityfocus.com/bid/108021","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-esa-filter-bypass","http://www.securityfocus.com/bid/108021","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-esa-filter-bypass"],"products":["cisco:email_security_appliance"],"source":"nvd","synced_at":"2026-10-19T20:56:19.218283075+00:00"},"epss":{"cve":"CVE-2019-1831","score":0.01647,"percentile":0.76468,"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."]}