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

Summary

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.

Timeline

1. Mar 4, 2026, 5:47 PM UTCCVE published
2. Mar 4, 2026, 9:30 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: partial

3. Mar 4, 2026, 9:30 PM UTCRecord last updated

Affected versions

• Cisco Cisco Cyber Vision

  3.0.0, 3.0.2, 3.0.3, 3.0.1, 3.1.0, 3.0.4, 3.1.1, 3.1.2, 3.2.0, 3.0.5, 3.2.1, 3.0.6, 3.2.2, 3.2.3, 3.2.4, 4.0.0, 4.0.1, 4.0.2, 4.0.3, 4.1.0, 4.1.1, 4.1.2, 4.1.3, 4.1.4, 4.2.0, 4.2.1, 4.1.5, 4.2.2, 4.2.X, 4.2.3, and 24 more

• Cisco Cisco Secure Firewall Threat Defense (FTD) Software

  7.2.0, 7.2.0.1, 7.2.1, 7.3.0, 7.2.2, 7.2.3, 7.3.1, 7.2.4, 7.2.5, 7.2.4.1, 7.3.1.1, 7.4.0, 7.2.5.1, 7.4.1, 7.2.6, 7.4.1.1, 7.2.7, 7.2.5.2, 7.3.1.2, 7.2.8, 7.6.0, 7.4.2, 7.2.8.1, 7.4.2.1, 7.2.9, 7.7.0, 7.4.2.2, 7.2.10, 7.6.1, 7.4.2.3, and 7 more

• Cisco Cisco UTD SNORT IPS Engine Software

  3.17.1S, 16.12.3, Fuji-16.9.5, 16.12.4, 17.3.1a, 16.6.6, 16.12.2, Fuji-16.9.6, 3.17.0S, Fuji-16.9.3, Denali-16.3.7, Fuji-16.9.2, Fuji-16.9.4, Everest-16.6.4, Everest-16.6.3, 16.6.5, Denali-16.3.5, 17.2.1r, 17.1.1, Everest-16.6.2, 16.6.7a, Denali-16.3.4, 16.6.1, Denali-16.3.9, Denali-16.3.3, 16.12.1a, 17.3.2, 17.4.1a, 16.12.5, 17.5.1, and 73 more

References 1