Vulnerability in Cisco Firepower Threat Defense Software
CVE-2025-20217
A vulnerability in the packet inspection functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to incorrect processing of traffic that is inspected by an affected device. An attacker could exploit this vulnerability by sending crafted traffic through the affected device. A successful exploit could allow the attacker to cause the affected device to enter an infinite loop while inspecting traffic, resulting in a DoS condition. The system watchdog will restart the Snort process automatically.
EPSS: 0.007 (50.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.
Affected products
- Cisco Firepower Threat Defense Software — versions 7.1.0, 7.1.0.1, 7.2.0
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2025-20217?
- CVE-2025-20217 is a high-severity vulnerability in Cisco Firepower Threat Defense Software, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 8.6/10. Published 2025-08-14.
- How severe is CVE-2025-20217?
- High severity. CVSS v3 base score is 8.6 out of 10.