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

> CVE-2017-12237: Cisco IOS and IOS XE Software Internet Key Exchange Denial-of-Service Vulnerability. CVSS 7.5 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2017-12237
Last updated: 2026-01-12T21:45:24Z

- Published: 2017-09-28 07:00 UTC · Updated: 2026-01-12 21:45 UTC · Assigner: cisco
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS: 7.1%, 94th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2022-03-03, federal due date 2022-03-24, ransomware use: Unknown
- CWE: CWE-399

## Description

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.

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- n/a: Cisco IOS and IOS XE

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2017-12237)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2017-12237)
- [https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-ike](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-ike)
- [http://www.securityfocus.com/bid/101037](http://www.securityfocus.com/bid/101037)
- [http://www.securitytracker.com/id/1039460](http://www.securitytracker.com/id/1039460)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2017-12237 · Markdown: https://rewindex.com/cve/CVE-2017-12237.md · JSON: https://rewindex.com/api/v1/cves/CVE-2017-12237 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:44:11.167Z