CVE-2026-20007
MediumCVSS 5.8Exploitation Probability (EPSS)
Low risk16th percentile - higher than 16% of all known CVEs
Summary
A vulnerability in the Snort 2 and Snort 3 deep packet inspection of Cisco Secure Firewall Threat Defense (FTD) Software allows an unauthenticated, remote attacker to bypass configured Snort rules and allow traffic onto the network that should have been dropped. This is due to a logic error in the integration of Snort Engine rules with FTD Software.
Risk Assessment
An attacker can bypass network security controls and introduce malicious traffic into the network, potentially leading to system compromise.
Recommendation
Apply security updates provided by Cisco for FTD software.
Other vulnerabilities in Cisco Secure Firewall Threat Defense
See all- CVE-2026-20064Medium
A vulnerability in Cisco Secure Firewall Threat Defense (FTD) Software allows an authenticated local attacker with a low-privileged account to cause the device to unexpectedly reload, resulting in a DoS condition. This is due to improper validation of user-supplied input.
- CVE-2026-20052Medium
A vulnerability in the memory management handling for the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software allows an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart. This is due to a logic error in memory management during SSL packet inspection. A successful exploit could cause a DoS condition.
- CVE-2026-20017Medium
A vulnerability in the CLI of Cisco Secure FTD Software allows an authenticated local attacker with administrative credentials to execute arbitrary commands on the underlying operating system as root. This is due to insufficient input validation of user-supplied command arguments.
- CVE-2026-20006Medium
A vulnerability in the TLS cryptography functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software allows an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to unexpectedly restart, resulting in a DoS condition. This is due to improper implementation of the TLS protocol. TLS 1.3 is not affected.
Original NVD description (English source)
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.