What is CVE-2016-6401?

CVE-2016-6401 is a medium-severity vulnerability in Cisco Carrier Routing System, classified under CWE-399. CVSS score: 5.3/10. Published 2016-09-17.

How severe is CVE-2016-6401?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Cisco Carrier Routing System

CVE-2016-6401

Cisco Carrier Routing System (CRS) 5.1 and 5.1.4, as used in CRS Carrier Grade Services for CRS-1 and CRS-3 devices, allows remote attackers to cause a denial of service (line-card reload) via crafted IPv6-over-MPLS packets, aka Bug ID CSCva32494.

Published 2016-09-17 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.008 (56.6th percentile), scored 2026-11-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 56.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Cisco Carrier Routing System — versions 5.1.4, 5.1_base

Weakness classification (CWE)

CWE-399

References

tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160914… (vendor-advisory, Vendor Advisory)
www.securitytracker.com/id/1036830 (vdb-entry)
www.securityfocus.com/bid/92964 (vdb-entry)

Frequently asked questions

What is CVE-2016-6401?: CVE-2016-6401 is a medium-severity vulnerability in Cisco Carrier Routing System, classified under CWE-399. CVSS score: 5.3/10. Published 2016-09-17.
How severe is CVE-2016-6401?: Medium severity. CVSS v3 base score is 5.3 out of 10.