Infinite loop in Cisco Firewall Threat Defense (FTD) - CVE-2025-20217
Published: August 15, 2025
Vulnerability identifier: #VU114108
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2025-20217
CWE-ID: CWE-835
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Cisco Systems, Inc
Affected software:
Cisco Firewall Threat Defense (FTD)
Cisco Firewall Threat Defense (FTD)
Detailed vulnerability description
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to infinite loop in the packet inspection functionality of the Snort 3 Detection Engine. A remote attacker can consume all available system resources and cause denial of service conditions.
How to mitigate CVE-2025-20217
Install update from vendor's website.