Denial‑of‑Service in Cisco IOS and IOS XE (CVE‑2018‑0159) Impacts IKEv1
What It Is – A flaw in the IKEv1 implementation of Cisco IOS and IOS XE can be triggered by an unauthenticated remote attacker, forcing the device to reload and causing a denial‑of‑service.
Exploitability – Publicly disclosed; proof‑of‑concept packets are available. CVSS v3.1 base score 7.5 (High).
Affected Products – Cisco IOS Software and Cisco IOS XE Software (all versions containing the vulnerable IKEv1 code).
Why It Matters for Trust & Control Assurance
- Demonstrates the need for a continuous patch‑management control that provides auditable evidence of timely remediation across network assets.
- Highlights the importance of availability monitoring (e.g., logging reload events) to detect and respond to service‑disruption attempts.
- Aligns with the control objective of maintaining resilient infrastructure, a single VCF control that maps to many frameworks (NIST CSF 2.0, ISO 27001, etc.).
Recommended Actions
- Inventory all Cisco IOS/IOS XE devices and verify firmware versions against Cisco’s advisory.
- Apply the Cisco‑released patches that address CVE‑2018‑0159 or upgrade to a non‑vulnerable release.
- Enable logging of IKEv1 session failures and device reloads; feed these logs into a SIEM for continuous monitoring.
- Document the remediation steps and retain patch‑install records as audit evidence of control compliance.
Source: CISA KEV – CVE‑2018‑0159