What is CVE-2017-6663?

CVE-2017-6663 is a medium-severity vulnerability in Cisco iOS. CVSS score: 6.5/10. Published 2017-08-07.

How severe is CVE-2017-6663?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Is CVE-2017-6663 known to be exploited?

Yes. CVE-2017-6663 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-03-03), indicating it is being actively exploited. 2 public proof-of-concept repositories are indexed.

Vulnerability in Cisco iOS

CVE-2017-6663

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.

Published 2017-08-07 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.021 (81.5th percentile), scored 2026-10-19.

Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 81.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.021 · newest: 0.021 · change: 0.000

Affected products

Cisco iOS — versions 15.6(1)t, 15.7\(3\)m, 15.3(3)s2
Cisco iOS Xe — versions 3.7.0e, 3.7.1e, 3.7.3e
Cisco iOS And Xe — versions Cisco IOS and IOS XE

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2022-03-03. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2022-03-24.

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

www.securitytracker.com/id/1038999 (VDB Entry, Third Party Advisory, vdb-entry, Broken Link)
tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170726… (Vendor Advisory)
www.securityfocus.com/bid/99973 (VDB Entry, Third Party Advisory, vdb-entry, Broken Link)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2017-6663?: CVE-2017-6663 is a medium-severity vulnerability in Cisco iOS. CVSS score: 6.5/10. Published 2017-08-07.
How severe is CVE-2017-6663?: Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2017-6663 known to be exploited?: Yes. CVE-2017-6663 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-03-03), indicating it is being actively exploited. 2 public proof-of-concept repositories are indexed.