{"cve":"CVE-2019-1981","nvd":{"published":"2019-11-05T20:15:11.783","modified":"2026-08-11T19:37:30.880","status":"Modified","description":"A vulnerability in the normalization functionality of Cisco Firepower Threat Defense Software, Cisco FirePOWER Services Software for ASA, and Cisco Firepower Management Center Software could allow an unauthenticated, remote attacker to bypass filtering protections. The vulnerability is due to insufficient normalization of a text-based payload. An attacker could exploit this vulnerability by sending traffic that contains specifically obfuscated payloads through an affected device. An exploit could allow the attacker to bypass filtering and deliver malicious payloads to protected systems that would otherwise be blocked.","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:L/A:N","score":5.8},"cwes":["CWE-20","CWE-264"],"references":["https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190816-ftd-null","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190816-ftd-null"],"products":["cisco:firepower_services_software_for_asa","cisco:secure_firewall_management_center","cisco:secure_firewall_threat_defense"],"source":"nvd","synced_at":"2026-10-19T20:59:25.448946135+00:00"},"epss":{"cve":"CVE-2019-1981","score":0.01042,"percentile":0.64058,"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."]}