{"id":"CVE-2018-0254","title":"A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass configured file action policies if an Intelligent Application Bypass (IAB) with a drop percentage thresh…","summary":"A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass configured file action policies if an Intelligent Application Bypass (IAB) with a drop percentage thresh…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","cwe":["CWE-693","CWE-693"],"vendor":"cisco","product":"secure_firewall_threat_defense","affected":["secure_firewall_threat_defense = 6.1.0.5","secure_firewall_threat_defense = 6.2.0.2","secure_firewall_threat_defense = 6.2.1","secure_firewall_threat_defense = 6.2.2"],"published":"2018-04-19","updated":"2026-08-11","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2018-0254","references":[{"url":"http://www.securityfocus.com/bid/103940","label":"psirt@cisco.com"},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180418-fss2","label":"psirt@cisco.com"},{"url":"http://www.securityfocus.com/bid/103940","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180418-fss2","label":"af854a3a-2127-422b-91ae-364da2661108"}],"tags":["nvd"],"epss":0.01365,"epssPercentile":0.70167,"ingestedAt":"2026-08-11T19:48:25.708Z","slug":"CVE-2018-0254","body":"## Overview\n\nA vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass configured file action policies if an Intelligent Application Bypass (IAB) with a drop percentage threshold is also configured. The vulnerability is due to incorrect counting of the percentage of dropped traffic. An attacker could exploit this vulnerability by sending network traffic to a targeted device. An exploit could allow the attacker to bypass configured file action policies, and traffic that should be dropped could be allowed into the network. Cisco Bug IDs: CSCvf86435.\n\n## Affected\n\n- `secure_firewall_threat_defense = 6.1.0.5`\n- `secure_firewall_threat_defense = 6.2.0.2`\n- `secure_firewall_threat_defense = 6.2.1`\n- `secure_firewall_threat_defense = 6.2.2`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.3,"exploitation":0,"ransomware":0},"changes":[]}