CVE-2024-20351
CVE-2024-20351 is a high-severity vulnerability in Cisco Firepower Threat Defense Software with a CVSS 3.x base score of 8.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.
Key facts
- Severity: High (CVSS 3.x base score 8.6)
- EPSS exploit prediction: 1% (50th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2024-18066
- Weakness: CWE-400
- Affected product: Cisco Firepower Threat Defense Software
- Published:
- Last modified:
Description
A vulnerability in the TCP/IP traffic handling function of the Snort Detection Engine of Cisco Firepower Threat Defense (FTD) Software and Cisco FirePOWER Services could allow an unauthenticated, remote attacker to cause legitimate network traffic to be dropped, resulting in a denial of service (DoS) condition. This vulnerability is due to the improper handling of TCP/IP network traffic. An attacker could exploit this vulnerability by sending a large amount of TCP/IP network traffic through the affected device. A successful exploit could allow the attacker to cause the Cisco FTD device to drop network traffic, resulting in a DoS condition. The affected device must be rebooted to resolve the DoS condition.
Frequently asked questions
- What is CVE-2024-20351?
- A vulnerability in the TCP/IP traffic handling function of the Snort Detection Engine of Cisco Firepower Threat Defense (FTD) Software and Cisco FirePOWER Services could allow an unauthenticated, remote attacker to cause legitimate network traffic to be dropped, resulting in a denial of service (DoS) condition. This vulnerability is due to the improper handling of TCP/IP network traffic. An attacker could exploit this vulnerability by sending a large amount of TCP/IP network traffic through the affected device. A successful exploit could allow the attacker to cause the Cisco FTD device to drop network traffic, resulting in a DoS condition. The affected device must be rebooted to resolve the DoS condition.
- How severe is CVE-2024-20351?
- CVE-2024-20351 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2024-20351 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2024-20351?
- CVE-2024-20351 primarily affects Cisco Firepower Threat Defense Software. In total, 85 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2024-20351?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2024-20351 have an EU (EUVD) identifier?
- Yes. CVE-2024-20351 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18066.
- When was CVE-2024-20351 published?
- CVE-2024-20351 was published on 2024-10-23 and last updated on 2026-06-17.
References
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-xss-yjj7ZjVq
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-xss-M446vbEO
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sa-ftd-snort-fw-BCJTZPMu
- https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75300
Affected products (85)
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.3:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.4:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.5:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.6:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.7:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.8:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.9:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.10:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.11:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.12:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.13:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.14:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.15:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.16:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.17:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.18:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.3:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.4:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.5:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.6:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.7:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.8:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.9:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.10:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.11:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.12:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.13:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.14:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.15:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.16:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.17:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.18:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.0.1:*:*:*:*:*:*:*
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