CVE-2026-20058
Cisco Secure Firewall Threat Defense Software Snort 3 Visual Basic for Application Denial of Service Vulnerability
Description
Multiple Cisco products are affected by vulnerabilities in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash. These vulnerabilities are due to improper error checking when decompressing VBA data. An attacker could exploit these vulnerabilities by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to unexpectedly restart, causing a DoS condition.
Weakness: CWE-786
Affected products
| Vendor | Product | Category | Matched by |
|---|---|---|---|
| Cisco | Cisco Firepower Threat Defense (FTD) Check your version | Firewall / NGFW | cna-assigner |
| Cisco | Cisco UTD SNORT IPS Engine | Threat Detection & Sandbox | cna-assigner |
Vendor-reported products (2)
- Cisco · Cisco Secure Firewall Threat Defense (FTD) Software
- Cisco · Cisco UTD SNORT IPS Engine Software
Vendor advisory
cisco-sa-ftd-snort3-vbavuls-96UcVVed
Multiple Cisco Products Snort 3 Visual Basic for Applications Denial of Service Vulnerabilities
Cisco’s rating: Medium (advisory CVSS 5.8) · Published Mar 4, 2026
Bug IDs: CSCwq23369 , CSCwq23372 , CSCwq23373 , CSCwq23377 , CSCwq97494 , CSCwq97497 , CSCwq97658 , CSCwq97660 , CSCwq97748 , CSCwq97750 , CSCwr21406
The vendor’s rating applies to the whole advisory and can differ from this CVE’s own CVSS severity. Where this comes from