A vulnerability in the Snort 2 and Snort 3 TCP and UDP detection engine of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Appliances could allow an unauthenticated, remote attacker to cause memory corruption, which could cause the Snort detection engine to restart unexpectedly. This vulnerability is due to improper memory management when the Snort detection engine processes specific TCP or UDP packets. An attacker could exploit this vulnerability by sending crafted TCP or UDP packets through a device that is inspecting traffic using the Snort detection engine. A successful exploit could allow the attacker to restart the Snort detection engine repeatedly, which could cause a denial of service (DoS) condition. The DoS condition impacts only the traffic through the device that is examined by the Snort detection engine. The device can still be managed over the network. Note: Once a memory block is corrupted, it cannot be cleared until the Cisco Firepower 2100 Series Appliance is manually reloaded. This means that the Snort detection engine could crash repeatedly, causing traffic that is processed by the Snort detection engine to be dropped until the device is manually reloaded.
Conclusion & alert: CVE-2024-20330 is rated Moderate Risk (53.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.32%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-03-16 | 0.19% | 0.32% | +0.13% |
| 2 | 2025-12-01 | 0.15% | 0.19% | +0.05% |
| 3 | 2025-11-21 | — | 0.15% | — |
Full EPSS history (8 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.6 | 3.1 | HIGH |
|
3.9 | 4.0 | [email protected] |
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| cisco | firepower_threat_defense | 7.0.0.0 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.0.0:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.0.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.0.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.1.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.1.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.2 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.2:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.2.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.2.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.3 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.3:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.4 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.4:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.5 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.5:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.6 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.6:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.6.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.6.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.6.2 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.6.2:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.0.6.3 | cpe:2.3:a:cisco:firepower_threat_defense:7.0.6.3:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.1.0 | cpe:2.3:a:cisco:firepower_threat_defense:7.1.0:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.1.0.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.1.0.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.1.0.3 | cpe:2.3:a:cisco:firepower_threat_defense:7.1.0.3:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.0 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.0:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.0.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.0.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.2 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.2:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.3 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.3:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.4 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.4:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.4.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.4.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.5 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.5:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.5.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.5.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.5.2 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.5.2:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.6 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.6:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.7 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.7:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.8 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.8:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.2.8.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.2.8.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.3.0 | cpe:2.3:a:cisco:firepower_threat_defense:7.3.0:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.3.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.3.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.3.1.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.3.1.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.3.1.2 | cpe:2.3:a:cisco:firepower_threat_defense:7.3.1.2:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.4.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.4.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.4.1.1 | cpe:2.3:a:cisco:firepower_threat_defense:7.4.1.1:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense | 7.4.2 | cpe:2.3:a:cisco:firepower_threat_defense:7.4.2:*:*:*:*:*:*:* |