Vulnerability · Published Mar 4, 2026 · Assigned by cisco
CVE-2026-20053Cisco Secure Firewall Threat Defense Software Snort 3 Visual Basic for Application Heap Overflow Denial of Service Vulnerability
Medium 5.8
In plain English
A medium-severity heap buffer overflow in Cisco Cyber Vision from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities).
Official 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 range checking when decompressing VBA data, which is user controlled. 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 an overflow of heap data, which could cause a DoS condition.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco Cyber Vision | 3.0.03.0.23.0.33.0.13.1.03.0.43.1.13.1.2 |
| Cisco | Cisco Secure Firewall Threat Defense (FTD) Software | 7.2.07.2.0.17.2.17.3.07.2.27.2.37.3.17.2.4 |
| Cisco | Cisco UTD SNORT IPS Engine Software | 17.12.1a17.9.417.12.217.13.1a17.12.317.14.1a17.12.417.12.3a |
Weakness: CWE-122 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L