Is CVE-2016-6393 being actively exploited?

CVE-2016-6393 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2016-6393?

CVE-2016-6393 has a CVSS 3.1 base score of 7.5 (HIGH).

CVE-2016-6393

HIGH · CVSS 7.5EPSS 4.6%EU EUVD

The AAA service in Cisco IOS 12.0 through 12.4 and 15.0 through 15.6 and IOS XE 2.1 through 3.18 and 16.2 allows remote attackers to cause a denial of service (device reload) via a failed SSH connection attempt that is mishandled during generation of an error-log message, aka Bug ID CSCuy87667.

Key facts

CVSS score: 7.5 (v3.1)
Severity: HIGH
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-399
EPSS score: 4.6% (92th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2016-7316)
Published: October 5, 2016
NVD last modified: June 17, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2016-7316 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.

View on the EU Vulnerability Database

Affected products

cisco / ios
cisco / ios xe
cisco / ios xe

Certified products that may be affected

9 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Cisco Catalyst 4500 Series Wired Access Switches running IOS-XE 3.10 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-10906-2018 - archived
Cisco Catalyst 3K/4K Wired Access Switches running IOS-XE 3.8.0E - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-10688-2016 - archived
Cisco Aggregation Services Router (ASR) 1000 Series, IOS XE 3.13 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-10609-2015 - archived
Cisco Integrated Services Router 4400 Series (ISR-4400), IOS XE 3.13.0 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-10600-2015 - archived
Cisco Catalyst 3650, 3850, 4500E (Sup7E, Sup7LE, Sup8E), 4500X, 4500XF running IOS-XE 3.6.1S - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-10607-2014 - archived

See all 9 in the Security Certifications Explorer.

References

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160928-aaados(Vendor Advisory)
http://www.securityfocus.com/bid/93196(Third Party Advisory, VDB Entry)
http://www.securitytracker.com/id/1036914(Third Party Advisory, VDB Entry)
https://ics-cert.us-cert.gov/advisories/ICSA-16-287-04(Third Party Advisory, US Government Resource)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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