How severe is CVE-2024-20307?

CVE-2024-20307 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2024-20307 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-2024-20307?

CVE-2024-20307 primarily affects Cisco Ios. In total, 365 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-20307?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2024-20307 have an EU (EUVD) identifier?

Yes. CVE-2024-20307 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18022.

When was CVE-2024-20307 published?

CVE-2024-20307 was published on 2024-03-27 and last updated on 2026-06-17.

CVE-2024-20307

CVE-2024-20307 is a medium-severity vulnerability in Cisco Ios with a CVSS 3.x base score of 6.8. 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-121.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-18022
Weakness: CWE-121
Affected product: Cisco Ios
Published: 2024-03-27
Last modified: 2026-06-17

Description

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 overflow, 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 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.

Frequently asked questions

What is CVE-2024-20307?: 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 overflow, 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 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.
How severe is CVE-2024-20307?: CVE-2024-20307 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-20307 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-2024-20307?: CVE-2024-20307 primarily affects Cisco Ios. In total, 365 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-20307?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-20307 have an EU (EUVD) identifier?: Yes. CVE-2024-20307 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18022.
When was CVE-2024-20307 published?: CVE-2024-20307 was published on 2024-03-27 and last updated on 2026-06-17.

References

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

Affected products (365)

cpe:2.3:o:cisco:ios:15.1\(2\)sg8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy9:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy10:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy11:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy12:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy13:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy14:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy15:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy16:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(1\)sy3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(1\)sy4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(1\)sy5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(1\)sy6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(1\)sy7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(1\)sy8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(3\)e4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(3\)e5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e5a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e9:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e10:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e10a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)e10d:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ea4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ea5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ea6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ea7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ea8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ea9:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ea9a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ec1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)ec2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(4\)m11:*:*:*:*:*:*:*

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