---
id: "CVE-2017-6663"
kind: "vulnerability"
aliases: ["CVE-2017-6663"]
title: "Cisco IOS and IOS XE Software: Cisco IOS Software and Cisco IOS XE Software Denial-of-Service Vulnerability"
severity: "high"
cvss: 6.5
epss: 0.02117
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Cisco IOS and IOS XE Software", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["cisco", "exploited", "infrastructure", "ios", "ios-xe", "network-gear"]
not_affected_if: ["autonomic-networking-disabled", "no-adjacent-attacker"]
published_at: "2017-08-07T06:29:00+00:00"
first_seen_at: "2026-10-23T19:11:52+00:00"
updated_at: "2026-10-23T21:57:35+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2017-6663", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2017-6663", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2017-6663", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Cisco IOS and IOS XE Software: Cisco IOS Software and Cisco IOS XE Software Denial-of-Service Vulnerability

Cisco IOS and IOS XE routers and switches with the Autonomic Networking feature can be made to reload by a crafted packet from an adjacent network host. An attacker gets a denial of service, not code execution or data access.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Cisco IOS and IOS XE Software affected ? fixed ?

## How to check

Run 'show running-config | include autonomic' on each Cisco IOS or IOS XE device to see whether Autonomic Networking is enabled.

## Fix

Apply the Cisco IOS and IOS XE updates per the vendor advisory; the fixed versions are not named in the sources.

## Timeline

- 2026-10-23T19:11:52+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2017-6663
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2017-6663
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2017-6663

## From the sources

A vulnerability in the Autonomic Networking feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause autonomic nodes of an affected system to reload, resulting in a denial of service (DoS) condition. More Information: CSCvd88936. Known Affected Releases: Denali-16.2.1 Denali-16.3.1.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_