CVE-2026-20218
A vulnerability in the Snort 3 Visual Basic for Applications (VBA) Decompression Engine of multiple Cisco products could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper range checking when Snort 3 decompresses VBA data, which is user controlled. An attacker could exploit this vulnerability by sending crafted VBA data to the Snort 3 Detection Engine of a targeted device. A successful exploit could allow the attacker to cause an overflow of stack data, which could result in a DoS condition.
Published:Oct 21, 2026
Last Modified:Oct 22, 2026
EPS:Oct 21, 2026
EPSS Score:0.00416
CVSS Score:5.8
Affected Products
Vendor
Product
Action
Vendor
Cisco
Product
Cisco Open Source Snort3
Cisco
Cisco Open Source Snort3
Vendor
Cisco
Product
Cisco Secure Firewall Threat Defense (ftd) Software
Cisco
Cisco Secure Firewall Threat Defense (ftd) Software
Vendor
Cisco
Product
Cisco Utd Snort Ips Engine Software
Cisco
Cisco Utd Snort Ips Engine Software
Vendor
Cisco
Product
Secure Firewall Threat Defense
Cisco
Secure Firewall Threat Defense
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
