CVE-2026-20054

Cisco Secure Firewall Threat Defense Software Snort 3 Visual Basic for Application Infinite Loop Denial of Service Vulnerability

Severity
Medium 5.8
CVSS 3.1
Exploited
Not listed
EPSS
0.004
35.5th percentile
Discovered by
Vendor
Published by the vendor
Published
Mar 4, 2026
Assigned by cisco

Description

Multiple Cisco products are affected by a vulnerability in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.  This vulnerability is due to improper error checking when decompressing VBA data. An attacker could exploit this vulnerability 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 enter an infinite loop, causing a DoS condition.

Weakness: CWE-835

Affected products

Vendor Product Category Matched by
Cisco Cisco Cyber Vision OT / IoT Security cna-assigner
Cisco Cisco Secure Firewall Firewall / NGFW cna-assigner
Cisco Cisco UTD SNORT IPS Engine Threat Detection & Sandbox cna-assigner
Vendor-reported affected versions (3)
  • Cisco · Cisco Cyber Vision
  • Cisco · Cisco Secure Firewall Threat Defense (FTD) Software
  • Cisco · Cisco UTD SNORT IPS Engine Software