CVE-2024-20342: Cisco Secure Firewall Threat Defense

High severity, CVSS 8.6. EPSS: 0.5% chance of exploitation in the next 30 days.

Multiple Cisco products are affected by a vulnerability in the rate filtering feature of the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured rate limiting filter.  This vulnerability is due to an incorrect connection count comparison. An attacker could exploit this vulnerability by sending traffic through an affected device at a rate that exceeds a configured rate filter. A successful exploit could allow the attacker to successfully bypass the rate filter. This could allow unintended traffic to enter the network protected by the affected device.

Affected products

• Cisco Secure Firewall Threat Defense: before 7.0.6.2 (fixed in 7.0.6.2); from 7.2.0, before 7.2.6 (fixed in 7.2.6); from 7.4.0, before 7.4.2 (fixed in 7.4.2); version 7.1.0 only; version 7.3.0 only
• Cisco Snort: from 3.0.0.0, before 3.1.74.0 (fixed in 3.1.74.0)

Published 2024-10-23. Last modified 2026-08-11.