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Firesight System SoftwareApplication · Cisco

CVE-2016-6420

MEDIUM · 6.5 CVSS v3.0 Published 2016-10-05
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Authorization bypass vulnerability in Cisco FireSIGHT System Software (versions 4.10.3 through 5.4.0) on Firepower Management Center allows remote authenticated users to craft HTTP requests that bypass authorization checks, enabling privilege escalation beyond the user's assigned permissions.

MitigationUpdate Cisco FireSIGHT/Firepower Management Center software to a version beyond 5.4.0 or apply the relevant Cisco security patch for CSCur25467. Review user accounts and authorization configurations for any anomalous privilege escalation.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Firesight System SoftwareApplication
Affected:= 4.10.3= 5.2.0= 5.3.0= 5.3.1= 5.4.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the FireSIGHT/Firepower Management Center software version
    Log into the Firepower Management Center web interface and navigate to Help > About, or access the CLI and run the command `show version` or `system firmware version` to retrieve the installed software version.
    Affected if The installed version is 4.10.3, 5.2.0, 5.3.0, 5.3.1, or any version in the range 4.10.3 through 5.4.0 (including intermediate versions not explicitly listed).
  2. Confirm the Firepower Management Center web interface is accessible
    Verify that the Firepower Management Center web interface (HTTPS on port 443) is reachable from the network. This is the component where the authorization bypass occurs.
    Affected if The Firepower Management Center web interface is exposed and the software version falls within the affected range.
  3. Check for existing user accounts with elevated permissions
    Review user accounts in the Firepower Management Center by navigating to System > Users > Users (or the equivalent user management page in your version). Document any accounts with administrative or elevated privileges.
    Affected if User accounts exist in the system and the software version is within the affected range, as an authenticated user could exploit the privilege escalation.
  4. Review authorization configuration for custom role definitions
    Inspect the authorization role configurations in the web interface under System > Users > User Roles (or similar) to identify any non-standard or custom roles that may have been created.
    Affected if Custom or non-default user roles exist and the software version is within the affected range, as the vulnerability allows bypassing authorization checks on role assignments.

A user is affected if the installed Cisco FireSIGHT/Firepower Management Center software version falls within the range 4.10.3 through 5.4.0 and the web interface is accessible to authenticated users.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update Cisco FireSIGHT/Firepower Management Center software to a version beyond 5.4.0 or apply the relevant Cisco security patch for CSCur25467. Review user accounts and authorization configurations for any anomalous privilege escalation.

Fix this in Firesight System Software Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing12.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,760
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2016-6420 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data