# CVE-2018-0159: Cisco IOS and XE Software Internet Key Exchange Version 1 Denial-of-Service Vulnerability

> CVE-2018-0159: Cisco IOS and XE Software Internet Key Exchange Version 1 Denial-of-Service Vulnerability. CVSS 7.5 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2018-0159
Last updated: 2026-01-12T21:55:25Z

- Published: 2018-03-28 22:00 UTC · Updated: 2026-01-12 21:55 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: 6.9%, 94th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2022-03-03, federal due date 2022-03-17, ransomware use: Unknown
- CWE: CWE-20

## Description

A vulnerability in the implementation of Internet Key Exchange Version 1 (IKEv1) functionality in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of specific IKEv1 packets. An attacker could exploit this vulnerability by sending crafted IKEv1 packets to an affected device during an IKE negotiation. A successful exploit could allow the attacker to cause an affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCuj73916.

## 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-2018-0159)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2018-0159)
- [https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ike-dos](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ike-dos)
- [http://www.securityfocus.com/bid/103562](http://www.securityfocus.com/bid/103562)
- [http://www.securitytracker.com/id/1040595](http://www.securitytracker.com/id/1040595)

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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-2018-0159 · Markdown: https://rewindex.com/cve/CVE-2018-0159.md · JSON: https://rewindex.com/api/v1/cves/CVE-2018-0159 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:49:22.787Z