Vulnerability · Published Mar 4, 2026 · Assigned by cisco
CVE-2026-20007Cisco Secure Firewall Threat Defense Software Snort Deep Inspection Bypass Vulnerability
Medium 5.8
In plain English
A medium-severity improper access control in Cisco Secure Firewall Threat Defense (FTD) Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities).
Official description
A vulnerability in the Snort 2 and Snort 3 deep packet inspection of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured Snort rules and allow traffic onto the network that should have been dropped. This vulnerability is due to a logic error in the integration of the Snort Engine rules with Cisco Secure FTD Software that could allow different Snort rules to be hit when deep inspection of the packet is performed for the inner and outer connections. An attacker could exploit this vulnerability by sending crafted traffic to a targeted device that would hit configured Snort rules. A successful exploit could allow the attacker to send traffic to a network where it should have been denied.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco Secure Firewall Threat Defense (FTD) Software | 6.4.0.16.4.0.26.4.0.56.4.06.4.0.36.4.0.46.4.0.66.4.0.7 |
Weakness: CWE-284 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N