A vulnerability in the IKEv1 fragmentation code of Cisco IOS...

6.8 CVSS

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2024-20307

Check My Exposure

Credits & Attribution

No credits recorded in the NVD database.

References

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

More from Cisco

View All →

CVE-2025-20393

Cisco Secure Email Gateway and Cisco Secure Email and Web Manager Remote Command Execution Vulnerability

Critical 10

CVE-2025-20377

Cisco Unified Intelligence Center API Information Disclosure Vulnerability

Medium 4.3

CVE-2025-20376

Cisco Unified Contact Center Express Remote Code Execution Vulnerability

Medium 6.5

CVE-2025-20375

Cisco Unified Contact Center Express Arbitrary File Upload Vulnerability

Medium 6.5

CVE-2025-20374

Cisco Unified Contact Center Express Arbitrary File Download Vulnerability

Medium 4.9

Affected Vendor

Cisco

View all reports →

Affected Software

IOS, Cisco IOS XE Software

Vulnerable Versions:

15.1(2)SG8, 15.2(4)M11, 15.1(2)SY8, 15.1(2)SY9, 15.1(2)SY10, 15.1(2)SY11, 15.1(2)SY12, 15.1(2)SY13, 15.1(2)SY14, 15.1(2)SY15, 15.1(2)SY16, 15.3(3)S8, 15.3(3)S9, 15.3(3)S10, 15.3(3)S8a, 15.2(4)E2, 15.2(3)E4, 15.2(5)E, 15.2(4)E3, 15.2(5b)E, 15.2(3)E5, 15.2(4)E4, 15.2(4)E5, 15.2(4)E5a, 15.2(4)E6, 15.2(4)E7, 15.2(4)E8, 15.2(4)E9, 15.2(4)E10, 15.2(4)E10a, 15.2(4)E10d, 15.4(3)S6, 15.4(3)S7, 15.4(3)S6a, 15.4(3)S8, 15.4(3)S9, 15.4(3)S10, 15.3(3)M8, 15.3(3)M9, 15.3(3)M10, 15.3(3)M8a, 15.2(1)SY3, 15.2(1)SY4, 15.2(1)SY5, 15.2(1)SY6, 15.2(1)SY7, 15.2(1)SY8, 15.5(3)S3, 15.5(1)S4, 15.5(2)S4, 15.5(3)S4, 15.5(3)S5, 15.5(3)S6, 15.5(3)S6a, 15.5(3)S7, 15.5(3)S6b, 15.5(3)S8, 15.5(3)S9, 15.5(3)S10, 15.5(3)S9a, 15.5(2)T4, 15.2(5)EA, 15.2(4)EA4, 15.2(4)EA5, 15.2(4)EA6, 15.2(4)EA7, 15.2(4)EA8, 15.2(4)EA9, 15.2(4)EA9a, 15.5(3)M3, 15.5(3)M4, 15.5(3)M4a, 15.5(3)M5, 15.5(3)M6, 15.5(3)M7, 15.5(3)M6a, 15.5(3)M8, 15.5(3)M9, 15.5(3)M10, 15.3(1)SY1, 15.3(1)SY2, 15.2(4)EC1, 15.2(4)EC2, 15.4(1)SY, 15.4(1)SY1, 15.4(1)SY2, 15.4(1)SY3, 15.4(1)SY4, 15.5(1)SY, 15.5(1)SY1, 15.5(1)SY2, 15.5(1)SY3, 15.5(1)SY4, 15.5(1)SY5, 15.5(1)SY6, 15.5(1)SY7, 15.5(1)SY8, 15.5(1)SY9, 15.5(1)SY10, 15.5(1)SY11, 15.7(3)M, 15.7(3)M1, 15.7(3)M0a, 15.7(3)M3, 15.7(3)M2, 15.7(3)M4, 15.7(3)M5, 15.7(3)M4a, 15.7(3)M4b, 15.7(3)M6, 15.7(3)M7, 15.7(3)M8, 15.7(3)M9, 15.8(3)M, 15.8(3)M1, 15.8(3)M0a, 15.8(3)M0b, 15.8(3)M2, 15.8(3)M1a, 15.8(3)M3, 15.8(3)M2a, 15.8(3)M4, 15.8(3)M3a, 15.8(3)M3b, 15.8(3)M5, 15.8(3)M6, 15.8(3)M7, 15.8(3)M8, 15.8(3)M9, 15.8(3)M10, 15.9(3)M, 15.9(3)M1, 15.9(3)M0a, 15.9(3)M2, 15.9(3)M3, 15.9(3)M2a, 15.9(3)M3a, 15.9(3)M4, 15.9(3)M3b, 15.9(3)M5, 15.9(3)M4a, 15.9(3)M6, 15.9(3)M7, 15.9(3)M6a, 15.9(3)M6b, 15.9(3)M7a, 15.3(3)JPI11, 3.4.8SG, 3.10.8S, 3.10.8aS, 3.10.9S, 3.10.10S, 3.13.6S, 3.13.7S, 3.13.6aS, 3.13.7aS, 3.13.8S, 3.13.9S, 3.13.10S, 3.14.4S, 3.15.4S, 3.7.4E, 3.7.5E, 3.16.3S, 3.16.3aS, 3.16.4S, 3.16.4aS, 3.16.4bS, 3.16.5S, 3.16.4dS, 3.16.6S, 3.16.7S, 3.16.6bS, 3.16.7aS, 3.16.7bS, 3.16.8S, 3.16.9S, 3.16.10S, 16.1.3, 16.2.1, 16.2.2, 3.8.2E, 3.8.3E, 3.8.4E, 3.8.5E, 3.8.5aE, 3.8.6E, 3.8.7E, 3.8.8E, 3.8.9E, 3.8.10E, 16.3.1, 16.3.2, 16.3.3, 16.3.1a, 16.3.4, 16.3.5, 16.3.5b, 16.3.6, 16.3.7, 16.3.8, 16.3.9, 16.3.10, 16.3.11, 16.4.1, 16.4.2, 16.4.3, 16.5.1, 16.5.1a, 16.5.1b, 16.5.2, 16.5.3, 3.9.0E, 16.6.1, 16.6.2, 16.6.3, 16.6.4, 16.6.5, 16.6.4a, 16.6.5a, 16.6.6, 16.6.7, 16.6.8, 16.6.9, 16.6.10, 16.7.1, 16.7.1a, 16.7.1b, 16.7.2, 16.7.3, 16.7.4, 16.8.1, 16.8.1a, 16.8.1b, 16.8.1s, 16.8.1c, 16.8.1d, 16.8.2, 16.8.1e, 16.8.3, 16.9.1, 16.9.2, 16.9.1a, 16.9.1b, 16.9.1s, 16.9.3, 16.9.4, 16.9.3a, 16.9.5, 16.9.5f, 16.9.6, 16.9.7, 16.9.8, 16.10.1, 16.10.1a, 16.10.1b, 16.10.1s, 16.10.1c, 16.10.1e, 16.10.1d, 16.10.2, 16.10.1f, 16.10.1g, 16.10.3, 16.11.1, 16.11.1a, 16.11.1b, 16.11.2, 16.11.1s, 16.12.1, 16.12.1s, 16.12.1a, 16.12.1c, 16.12.1w, 16.12.2, 16.12.1y, 16.12.2a, 16.12.3, 16.12.8, 16.12.2s, 16.12.1x, 16.12.1t, 16.12.4, 16.12.3s, 16.12.3a, 16.12.4a, 16.12.5, 16.12.6, 16.12.1z1, 16.12.5a, 16.12.5b, 16.12.1z2, 16.12.6a, 16.12.7, 16.12.9, 17.1.1, 17.1.1a, 17.1.1s, 17.1.1t, 17.1.3, 17.2.1, 17.2.1r, 17.2.1a, 17.2.1v, 17.2.2, 17.2.3, 17.3.1, 17.3.2, 17.3.3, 17.3.1a, 17.3.1w, 17.3.2a, 17.3.1x, 17.3.1z, 17.3.4, 17.3.5, 17.3.4a, 17.3.6, 17.3.4b, 17.3.4c, 17.3.5a, 17.3.5b, 17.3.7, 17.4.1, 17.4.2, 17.4.1a, 17.4.1b, 17.4.2a, 17.5.1, 17.5.1a, 17.6.1, 17.6.2, 17.6.1w, 17.6.1a, 17.6.1x, 17.6.3, 17.6.1y, 17.6.1z, 17.6.3a, 17.6.4, 17.6.1z1, 17.6.5, 17.6.5a, 17.7.1, 17.7.1a, 17.7.1b, 17.7.2, 17.10.1, 17.10.1a, 17.10.1b, 17.8.1, 17.8.1a, 17.9.1, 17.9.1w, 17.9.2, 17.9.1a, 17.9.1x, 17.9.1y, 17.9.3, 17.9.2a, 17.9.1x1, 17.9.3a, 17.11.1, 17.11.1a, 17.11.99SW