--- id: CVE-2026-20005 title: >- Multiple Cisco products are affected by a vulnerability in the Snort 3 Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspect… summary: >- Multiple Cisco products are affected by a vulnerability in the Snort 3 Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspect… severity: medium cvss: 5.8 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L' cwe: - CWE-392 vendor: cisco product: cyber_vision affected: - cyber_vision = 3.0.0 - cyber_vision = 3.0.1 - cyber_vision = 3.0.2 - cyber_vision = 3.0.3 - cyber_vision = 3.0.4 - cyber_vision = 3.0.5 - cyber_vision = 3.0.6 - cyber_vision = 3.1.0 - cyber_vision = 3.1.1 - cyber_vision = 3.1.2 - cyber_vision = 3.2.0 - cyber_vision = 3.2.1 - cyber_vision = 3.2.2 - cyber_vision = 3.2.3 - cyber_vision = 3.2.4 - cyber_vision = 4.0.0 - cyber_vision = 4.0.1 - cyber_vision = 4.0.2 - cyber_vision = 4.0.3 - cyber_vision = 4.1.0 - cyber_vision = 4.1.1 - cyber_vision = 4.1.2 - cyber_vision = 4.1.3 - cyber_vision = 4.1.4 - cyber_vision = 4.1.5 - cyber_vision = 4.1.6 - cyber_vision = 4.1.7 - cyber_vision = 4.2.0 - cyber_vision = 4.2.1 - cyber_vision = 4.2.2 - cyber_vision = 4.2.3 - cyber_vision = 4.2.4 - cyber_vision = 4.2.6 - cyber_vision = 4.3.0 - cyber_vision = 4.3.1 - cyber_vision = 4.3.2 - cyber_vision = 4.3.3 - cyber_vision = 4.4.0 - cyber_vision = 4.4.1 - cyber_vision = 4.4.2 - cyber_vision = 4.4.3 - cyber_vision = 5.0.0 - cyber_vision = 5.0.1 - cyber_vision = 5.0.2 - cyber_vision = 5.1.0 - cyber_vision = 5.1.1 - cyber_vision = 5.1.2 - cyber_vision = 5.1.3 - cyber_vision = 5.2.0 - cyber_vision = 5.2.1 - cyber_vision = 5.3.0 - cyber_vision = 5.3.1 - cyber_vision = 5.3.2 - secure_firewall_threat_defense = 7.6.0 - secure_firewall_threat_defense = 7.6.1 - secure_firewall_threat_defense = 7.6.2 - secure_firewall_threat_defense = 7.6.2.1 - secure_firewall_threat_defense = 7.7.0 - secure_firewall_threat_defense = 7.7.10 - secure_firewall_threat_defense = 7.7.10.1 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.9.4 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.9.5e - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.1a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.2 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.3 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.3a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.4 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.4a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.4b - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5b - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5c - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5d - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.6 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.13.1a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.14.1a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.1a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.2a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.2c - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.3 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.3a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.4 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.4c - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.16.1a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.17.1 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.18.1 - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.18.1a - unified_threat_defense_snort_intrusion_prevention_system_engine = 17.18.2 - 'snort >= 3.0.0-233, < 3.9.2.0' patched: - snort 3.9.2.0 published: '2026-03-04' updated: '2026-09-01' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-20005' references: - url: >- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort3-multi-dos-XFWkWSwz label: psirt@cisco.com - url: 'https://software.cisco.com' tags: - nvd - csaf - vendor-advisory - cisco epss: 0.00521 epssPercentile: 0.44016 ingestedAt: '2026-09-01T20:32:01.233Z' --- ## Overview Multiple Cisco products are affected by a vulnerability in the Snort 3 Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to incomplete parsing of the SSL handshake ingress packets. An attacker could exploit this vulnerability by sending crafted SSL handshake packets. A successful exploit could allow the attacker to cause a denial of service (DoS) condition when the Snort 3 Detection Engine restarts unexpectedly. ## Affected - `cyber_vision = 3.0.0` - `cyber_vision = 3.0.1` - `cyber_vision = 3.0.2` - `cyber_vision = 3.0.3` - `cyber_vision = 3.0.4` - `cyber_vision = 3.0.5` - `cyber_vision = 3.0.6` - `cyber_vision = 3.1.0` - `cyber_vision = 3.1.1` - `cyber_vision = 3.1.2` - `cyber_vision = 3.2.0` - `cyber_vision = 3.2.1` - `cyber_vision = 3.2.2` - `cyber_vision = 3.2.3` - `cyber_vision = 3.2.4` - `cyber_vision = 4.0.0` - `cyber_vision = 4.0.1` - `cyber_vision = 4.0.2` - `cyber_vision = 4.0.3` - `cyber_vision = 4.1.0` - `cyber_vision = 4.1.1` - `cyber_vision = 4.1.2` - `cyber_vision = 4.1.3` - `cyber_vision = 4.1.4` - `cyber_vision = 4.1.5` - `cyber_vision = 4.1.6` - `cyber_vision = 4.1.7` - `cyber_vision = 4.2.0` - `cyber_vision = 4.2.1` - `cyber_vision = 4.2.2` - `cyber_vision = 4.2.3` - `cyber_vision = 4.2.4` - `cyber_vision = 4.2.6` - `cyber_vision = 4.3.0` - `cyber_vision = 4.3.1` - `cyber_vision = 4.3.2` - `cyber_vision = 4.3.3` - `cyber_vision = 4.4.0` - `cyber_vision = 4.4.1` - `cyber_vision = 4.4.2` - `cyber_vision = 4.4.3` - `cyber_vision = 5.0.0` - `cyber_vision = 5.0.1` - `cyber_vision = 5.0.2` - `cyber_vision = 5.1.0` - `cyber_vision = 5.1.1` - `cyber_vision = 5.1.2` - `cyber_vision = 5.1.3` - `cyber_vision = 5.2.0` - `cyber_vision = 5.2.1` - `cyber_vision = 5.3.0` - `cyber_vision = 5.3.1` - `cyber_vision = 5.3.2` - `secure_firewall_threat_defense = 7.6.0` - `secure_firewall_threat_defense = 7.6.1` - `secure_firewall_threat_defense = 7.6.2` - `secure_firewall_threat_defense = 7.6.2.1` - `secure_firewall_threat_defense = 7.7.0` - `secure_firewall_threat_defense = 7.7.10` - `secure_firewall_threat_defense = 7.7.10.1` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.9.4` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.9.5e` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.1a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.2` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.3` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.3a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.4` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.4a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.4b` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5b` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5c` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.5d` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.12.6` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.13.1a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.14.1a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.1a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.2a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.2c` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.3` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.3a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.4` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.15.4c` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.16.1a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.17.1` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.18.1` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.18.1a` - `unified_threat_defense_snort_intrusion_prevention_system_engine = 17.18.2` - `snort >= 3.0.0-233, < 3.9.2.0` ## Remediation Upgrade past the affected range: - `snort 3.9.2.0` ## Vendor advisories - **cisco-sa-snort3-multi-dos-XFWkWSwz** · Cisco · affected: Cisco UTD SNORT IPS Engine Software (26 versions), Cisco Firepower 1000 Series, Cisco 3000 Series Industrial Security Appliances (ISA), Cisco Firepower 9000 Series, Cisco Firepower 4100 Series, Cisco Secure Firewall Threat Defense Virtual, … · updated 2026-03-04 · [advisory](https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort3-multi-dos-XFWkWSwz)