CVE-2018-0158 remediation guide
Cisco IOS Software and Cisco IOS XE Software
A vulnerability in the Internet Key Exchange Version 2 (IKEv2) module of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a memory leak or a reload of an affected device that leads to a denial of service (DoS) condition. The vulnerability is due to incorrect processing of certain IKEv2 packets. An attacker could exploit this vulnerability by sending crafted IKEv2 packets to an affected device to be processed. A successful exploit could cause an affected device to continuously consume memory and eventually reload, resulting in a DoS condit...
A verified fixed-version field is not available. Use the linked NVD and supporting references, then confirm the vendor-supported path before changing production systems.
Identify the affected asset
Confirm whether Cisco IOS Software and Cisco IOS XE Software is installed, record the deployed version and installation path, and identify exposed interfaces.
- Record the product name, package or appliance identifier, and installed version.
- Identify internet-facing, administrative, API, and internal access paths.
- Preserve the pre-change configuration and relevant service logs.
Validate the affected-version match
Compare the deployed version with the affected range: Cisco IOS and IOS XE, 15.5(3)s1.1, 15.5(3)s1.2, 15.5(3)s1.4, 15.5(3)s1.5, 15.5(3)s1.7, 15.5(3)s1.8, 15.5(3)s1.9, 15.5(3)s1.10, 15.5(3)s1.11, 15.5(3)s1.12. Treat incomplete inventory results as unresolved.
Prioritize with independent signals
CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog. Combine this signal with asset criticality, exposure, compensating controls, and business impact.
Apply supported remediation
Apply updates per vendor instructions.
Verify the result
Confirm the resulting version, service health, authentication and access paths, monitoring coverage, and relevant security logs.
- Confirm the expected version and package state.
- Run a functional health check for critical service paths.
- Review authentication, error, application, and security monitoring logs.
- Reassess exposure if the supported fix cannot be applied.
Operational boundary
This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.