Vulnerability · CVE-2017-12237
Cisco IOS and IOS XE Software Internet Key Exchange Denial-of-Service Vulnerability
Published Sep 28, 2017 · catalog updated Jun 16, 2026 · Cisco IOS and IOS XE Software
Patch now
CVE-2017-12237 is in the CISA known-exploited catalog, due Mar 24, 2022. Confirm Cisco IOS and IOS XE Software against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- Severity
- High7.5
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 7.07%
- Remediation
- Remediation guidance
- Affected products
- cpe cisco/ios · cpe cisco/ios xe · vendor Cisco IOS and IOS XE Software
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe cisco/iosversion unspecified
- cpe cisco/ios xeversion unspecified
- vendor Cisco IOS and IOS XE Softwareversion unspecified
How to fix CVE-2017-12237
Recommended remediation
Apply updates per vendor instructions. CISA due date Mar 24, 2022.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2017-12237 is in the CISA known-exploited catalog, due Mar 24, 2022. Confirm Cisco IOS and IOS XE Software against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Affected version ranges are not on this record. Apply updates per vendor instructions.
What should an analyst verify?
CWE-399. EPSS 7.07%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Technology hubs
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Sep 28, 2017 · Catalog
Detected
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 packet
Mar 3, 2022 · CISA KEV
Known exploited
Apply updates per vendor instructions.
Mar 24, 2022 · CISA KEV
Remediation due
Apply updates per vendor instructions.
Jun 16, 2026 · Catalog
Updated
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 packet
Sources
- CISA KEVConfirmed exploitationCVE-2017-12237
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.
cisa.gov - CVE.orgVulnerability recordCVE-2017-12237
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2017-12237
30-day exploitation probability 7.1%
first.org - NIST NVDVulnerability recordCVE-2017-12237
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 t
nvd.nist.gov - VulnCheck KEVConfirmed exploitationCVE-2017-12237
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.
vulncheck.com
References
Freshness
Last verified in this catalog Oct 17, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.