What is CVE-2016-6420?

CVE-2016-6420 is a medium-severity vulnerability in Cisco Firesight System Software, classified under Information Disclosure. CVSS score: 6.5/10. Published 2016-10-05.

How severe is CVE-2016-6420?

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

Information disclosure in Cisco Firesight System Software

CVE-2016-6420

Cisco FireSIGHT System Software 4.10.3 through 5.4.0 in Firepower Management Center allows remote authenticated users to bypass authorization checks and gain privileges via a crafted HTTP request, aka Bug ID CSCur25467.

Vulnerability class: Information Disclosure

Published 2016-10-05 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.018 (78.1th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 78th percentile — 78.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.018 · newest: 0.018 · change: 0.000

Affected products

Cisco Firesight System Software — versions 4.10.3, 5.2.0, 5.3.0

Weakness classification (CWE)

References

www.securitytracker.com/id/1036919 (vdb-entry)
www.securityfocus.com/bid/93204 (vdb-entry)
tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160928… (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2016-6420?: CVE-2016-6420 is a medium-severity vulnerability in Cisco Firesight System Software, classified under Information Disclosure. CVSS score: 6.5/10. Published 2016-10-05.
How severe is CVE-2016-6420?: Medium severity. CVSS v3 base score is 6.5 out of 10.