CVE-2024-20426
CVE-2024-20426 is a high-severity vulnerability in Cisco Adaptive Security Appliance 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-476.
Key facts
- Severity: High (CVSS 3.x base score 8.6)
- EPSS exploit prediction: 1% (42nd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2024-18141
- Weakness: CWE-476
- Affected product: Cisco Adaptive Security Appliance Software
- Published:
- Last modified:
Description
A vulnerability in the Internet Key Exchange version 2 (IKEv2) protocol for VPN termination of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower 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 insufficient input validation. An attacker could exploit this vulnerability by sending crafted IKEv2 traffic to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Frequently asked questions
- What is CVE-2024-20426?
- A vulnerability in the Internet Key Exchange version 2 (IKEv2) protocol for VPN termination of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower 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 insufficient input validation. An attacker could exploit this vulnerability by sending crafted IKEv2 traffic to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
- How severe is CVE-2024-20426?
- CVE-2024-20426 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-2024-20426 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2024-20426?
- CVE-2024-20426 primarily affects Cisco Adaptive Security Appliance Software. In total, 54 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2024-20426?
- 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-2024-20426 have an EU (EUVD) identifier?
- Yes. CVE-2024-20426 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18141.
- When was CVE-2024-20426 published?
- CVE-2024-20426 was published on 2024-10-23 and last updated on 2026-06-17.
References
Affected products (54)
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.1.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2.5:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2.7:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2.8:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.3.39:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.3.46:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.3.53:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.3.55:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.3.56:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.4:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.4.5:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.4.8:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.4.22:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.4.24:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.4.29:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.5:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.9:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.12:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.18:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.22:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.24:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.27:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.28:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.19.1.31:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.20.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.20.1.5:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.20.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.20.2.10:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.20.2.21:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.0.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.3:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.4:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.4.1:*:*:*:*:*:*:*
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