{"id":"CVE-2021-1223","title":"Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP","summary":"Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The vulnerability is due to incorrect handling of an …","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","cwe":["CWE-693"],"vendor":"cisco","product":"secure_firewall_management_center","affected":["secure_firewall_management_center = 2.9.14.0","secure_firewall_management_center = 2.9.15","secure_firewall_management_center = 2.9.16","secure_firewall_threat_defense < 6.7.0","ios_xe < 17.4.1","snort < 2.9.17"],"patched":["secure_firewall_threat_defense 6.7.0","ios_xe 17.4.1","snort 2.9.17"],"published":"2021-01-13","updated":"2026-08-11","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-1223","references":[{"url":"https://lists.debian.org/debian-lts-announce/2023/02/msg00011.html","label":"psirt@cisco.com"},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-filepolbypass-67DEwMe2","label":"psirt@cisco.com"},{"url":"https://www.debian.org/security/2023/dsa-5354","label":"psirt@cisco.com"},{"url":"https://lists.debian.org/debian-lts-announce/2023/02/msg00011.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-filepolbypass-67DEwMe2","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2023/dsa-5354","label":"af854a3a-2127-422b-91ae-364da2661108"}],"tags":["nvd"],"epss":0.01985,"epssPercentile":0.79447,"ingestedAt":"2026-08-18T12:28:06.756Z","slug":"CVE-2021-1223","body":"## Overview\n\nMultiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The vulnerability is due to incorrect handling of an HTTP range header. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass configured file policy for HTTP packets and deliver a malicious payload.\n\n## Affected\n\n- `secure_firewall_management_center = 2.9.14.0`\n- `secure_firewall_management_center = 2.9.15`\n- `secure_firewall_management_center = 2.9.16`\n- `secure_firewall_threat_defense < 6.7.0`\n- `ios_xe < 17.4.1`\n- `snort < 2.9.17`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `secure_firewall_threat_defense 6.7.0`\n- `ios_xe 17.4.1`\n- `snort 2.9.17`","depth":"twilight","depthScore":42,"depthScoreParts":{"impact":41.3,"likelihood":0.4,"exploitation":0,"ransomware":0},"changes":[]}