Medium [CVE-2026-20007] Cisco Secure Firewall Threat Defense Software Snort Deep Inspection Bypass Vulnerability
This medium-severity Cisco advisory covers CVE-2026-20007 affecting Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1, Cisco Secure Firewall Threat Defense (FTD) Software 7.0.1.1, Cisco Secure Firewall Threat Defense (FTD) Software 7.0.2.1.
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Summary
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…
Affected products named by the advisory: Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.1.1; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.2.1; Cisco Secure Firewall Threat Defense (FTD) Software 7.0.3; and 3 more.
- Scope: At the time of publication, this vulnerability affected Cisco devices if they were running a vulnerable release of Cisco Secure FTD Software and had an intrusion policy enabled that had a Snort Detection Engine running.
Official advisory · high-confidence parse· fetched 2 months ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 2 months ago·verify at source
Mitigation checklist
- There are no workarounds that address this vulnerability.
Official advisory · high-confidence parse· fetched 2 months ago·verify at source
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