CVE-2026-20067
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 error checking when parsing the Multicast DNS fields of the HTTP header. An attacker could exploit this vulnerability by sending crafted HTTP packets through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause a DoS condition when the Snort 3 Detection Engine unexpectedly restarts.
Published:Mar 4, 2026
Last Modified:Aug 19, 2026
EPS:Mar 4, 2026
EPSS Score:0.00475
CVSS Score:5.8
Affected Products
Vendor
Product
Action
Vendor
Cisco
Product
Cisco Utd Snort Ips Engine Software
Cisco
Cisco Utd Snort Ips Engine Software
Vendor
Cisco
Product
Cyber Vision
Cisco
Cyber Vision
Vendor
Cisco
Product
Secure Firewall Threat Defense
Cisco
Secure Firewall Threat Defense
Vendor
Cisco
Product
Snort
Cisco
Snort
Vendor
Cisco
Product
Unified Threat Defense Snort Intrusion Prevention System Engine
Cisco
Unified Threat Defense Snort Intrusion Prevention System Engine
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
No CAPEC recorded yet
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
