Is CVE-2024-20308 being actively exploited?

CVE-2024-20308 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2024-20308?

CVE-2024-20308 has a CVSS 3.1 base score of 8.6 (HIGH).

CVE-2024-20308

HIGH · CVSS 8.6EPSS 0.8%EU EUVD

A vulnerability in the IKEv1 fragmentation code of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a heap underflow, resulting in an affected device reloading. This vulnerability exists because crafted, fragmented IKEv1 packets are not properly reassembled. An attacker could exploit this vulnerability by sending crafted UDP packets to an affected system. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: Only traffic that is directed to the affected system can be used to exploit this vulnerability. This vulnerability can be triggered by IPv4 and IPv6 traffic..

Key facts

CVSS score: 8.6 (v3.1)
Severity: HIGH
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Weakness (CWE): CWE-787
EPSS score: 0.8% (56th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2024-18023)
Published: March 27, 2024
NVD last modified: June 17, 2026
Status: Analyzed

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2024-18023 in the EU Vulnerability Database. Last updated in EUVD on November 26, 2024.

View on the EU Vulnerability Database

Affected products

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and 950 more…

Certified products that may be affected

11 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Cisco Embedded Services 9300 and 3300 Series Switches (ESS9300 & ESS3300) running IOS-XE 17.12 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-11521-2025 - active
Cisco cEdge Routers running IOS XE 17.12 with SD-WAN 20.12 - Cisco Systems, Inc. - Common Criteria 654-LSS - active
Cisco Catalyst Industrial Ethernet 3100 (IE3100) Rugged Series Switches running IOS-XE 17.12 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-11490-2024 - archived
Cisco Catalyst Industrial Ethernet 9300 Rugged Series Switches running IOS-XE 17.12 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-11466-2024 - archived
Cisco Catalyst Industrial Ethernet 3200, 3300, 3400, 3400H (IE3x00) Rugged Series Switches running IOS-XE 17.12 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-11443-2024 - archived

See all 11 in the Security Certifications Explorer.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ikev1-NO2ccFWz(Vendor Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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