# CVE-2018-0171: Cisco IOS and IOS XE Software Smart Install Remote Code Execution Vulnerability

Source: https://junglewise.ai/threats/cve-2018-0171-cisco-ios-and-ios-xe-software-smart-install-remote-code-execution  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2018-0171 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2021-11-03

A vulnerability in the Smart Install feature of Cisco IOS and IOS XE Software allows an unauthenticated, remote attacker to trigger a buffer overflow by sending crafted packet data to TCP port 4786. Successful exploitation can lead to arbitrary code execution, a device reload, or an indefinite loop causing a watchdog crash.

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

## Quick answers

**Is CVE-2018-0171 exploited in the wild?** Yes. CVE-2018-0171 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2018-0171?** Critical severity, with a CVSS score of 9.8, published 3 November 2021.

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

**Is there a fix for CVE-2018-0171?** 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-2018-0171 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2018-0171?** Check whether you run Cisco IOS or Cisco IOS XE. 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
- Cisco IOS XE

## Timeline

- 2018-03-28: disclosed: Initial Cisco Security Advisory published
- 2018-04-24: other: Initial NVD analysis completed
- 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2021-11-03: exploited: Confirmed exploited in the wild per CISA KEV entry

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