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

Source: https://junglewise.ai/threats/cve-2018-0159-cisco-ios-and-xe-software-internet-key-exchange-version-1-denial  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-03-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2018-0159 · Severity: critical · CVSS 7.5 · Exploited in the wild · Published 2022-03-03

A vulnerability in the IKEv1 implementation of Cisco IOS and IOS XE Software allows an unauthenticated remote attacker to cause a device reload. The issue is caused by improper validation of crafted IKEv1 packets sent during negotiation, leading to a denial-of-service condition.

Technologies: [Cisco IOS](https://junglewise.ai/threats/technologies/ios), [Cisco Ios Software](https://junglewise.ai/threats/technologies/ios-software), [Cisco IOS XE](https://junglewise.ai/threats/technologies/ios-xe), [Cisco IOS XE Software](https://junglewise.ai/threats/technologies/ios-xe-software). Vendors: [Cisco](https://junglewise.ai/threats/vendors/cisco).

## Quick answers

**Is CVE-2018-0159 exploited in the wild?** Yes. CVE-2018-0159 is known to be exploited in the wild, first recorded on 3 March 2022. Treat it as urgent.

**How severe is CVE-2018-0159?** Critical severity, with a CVSS score of 7.5, published 3 March 2022.

**Which products and versions are affected?** Cisco IOS Software; Cisco IOS XE Software.

**Is there a fix for CVE-2018-0159?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2018-0159 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2018-0159?** Check whether you run Cisco IOS, Cisco Ios Software, Cisco IOS XE or one of the others listed. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Cisco IOS Software
- Cisco IOS XE Software

## Timeline

- 2018-03-28: advisory: Initial Cisco security advisory published
- 2022-03-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2022-03-03: disclosed: NVD publication date
- 2022-03-03: exploited: Confirmed as exploited in the wild per CISA KEV catalog

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