CVE-2017-12237: Cisco IOS and IOS XE Software Internet Key Exchange Denial-of-Service Vulnerability

CISA Known Exploited Vulnerabilities

Name

Cisco IOS and IOS XE Software Internet Key Exchange Denial-of-Service Vulnerability

Vendor

Cisco

Product

IOS and IOS XE Software

Added to the catalog

2022-03-03

Due date for US federal agencies

2022-03-24

Weaknesses

CWE-399

Catalog version

2026.10.30

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) module of Cisco IOS and Cisco IOS XE could allow an unauthenticated, remote attacker to cause high CPU utilization, traceback messages, or a reload of an affected device that leads to a denial of service.

Required action (CISA)

Apply updates per vendor instructions.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

• https://nvd.nist.gov/vuln/detail/CVE-2017-12237

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status

Analyzed

Published

2017-09-29T01:34:48.967

Last modified

2026-06-17T01:02:56.737

Weaknesses

CWE-399, NVD-CWE-noinfo

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) module of Cisco IOS 15.0 through 15.6 and Cisco IOS XE 3.5 through 16.5 could allow an unauthenticated, remote attacker to cause high CPU utilization, traceback messages, or a reload of an affected device that leads to a denial of service (DoS) condition. The vulnerability is due to how an affected device processes certain IKEv2 packets. An attacker could exploit this vulnerability by sending specific IKEv2 packets to an affected device to be processed. A successful exploit could allow the attacker to cause high CPU utilization, traceback messages, or a reload of the affected device that leads to a DoS condition. This vulnerability affects Cisco devices that have the Internet Security Association and Key Management Protocol (ISAKMP) enabled. Although only IKEv2 packets can be used to trigger this vulnerability, devices that are running Cisco IOS Software or Cisco IOS XE Software are vulnerable when ISAKMP is enabled. A device does not need to be configured with any IKEv2-specific features to be vulnerable. Many features use IKEv2, including different types of VPNs such as the following: LAN-to-LAN VPN; Remote-access VPN, excluding SSL VPN; Dynamic Multipoint VPN (DMVPN); and FlexVPN. Cisco Bug IDs: CSCvc41277.

References

• http://www.securityfocus.com/bid/101037 (Broken Link, Third Party Advisory, VDB Entry)
• http://www.securitytracker.com/id/1039460 (Broken Link, Third Party Advisory, VDB Entry)
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-ike (Vendor Advisory)
• http://www.securityfocus.com/bid/101037 (Broken Link, Third Party Advisory, VDB Entry)
• http://www.securitytracker.com/id/1039460 (Broken Link, Third Party Advisory, VDB Entry)
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-ike (Vendor Advisory)
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12237 (US Government Resource)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:41:35.381Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2017-12237

CVE record

Assigner

cisco

State

PUBLISHED

Published

2017-09-28T07:00:00.000Z

Updated

2026-01-12T21:45:24.703Z

Problem types

CWE-399

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) module of Cisco IOS 15.0 through 15.6 and Cisco IOS XE 3.5 through 16.5 could allow an unauthenticated, remote attacker to cause high CPU utilization, traceback messages, or a reload of an affected device that leads to a denial of service (DoS) condition. The vulnerability is due to how an affected device processes certain IKEv2 packets. An attacker could exploit this vulnerability by sending specific IKEv2 packets to an affected device to be processed. A successful exploit could allow the attacker to cause high CPU utilization, traceback messages, or a reload of the affected device that leads to a DoS condition. This vulnerability affects Cisco devices that have the Internet Security Association and Key Management Protocol (ISAKMP) enabled. Although only IKEv2 packets can be used to trigger this vulnerability, devices that are running Cisco IOS Software or Cisco IOS XE Software are vulnerable when ISAKMP is enabled. A device does not need to be configured with any IKEv2-specific features to be vulnerable. Many features use IKEv2, including different types of VPNs such as the following: LAN-to-LAN VPN; Remote-access VPN, excluding SSL VPN; Dynamic Multipoint VPN (DMVPN); and FlexVPN. Cisco Bug IDs: CSCvc41277.

References

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-ike
• 1039460
• 101037

Read on 2026-11-03T00:34:54.103Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2017/12xxx/CVE-2017-12237.json