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Secure Firewall Management CenterApplication · Cisco

CVE-2020-3499

HIGH · 8.6 CVSS v3.1 Published 2020-10-21
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
95/100
Remediation priority · Urgent
Remotely reachable No privileges 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
A vulnerability in the licensing service of Cisco Firepower Management Center (FMC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.The vulnerability is due to improper handling of system resource values by the affected system. An attacker could exploit this vulnerability by sending malicious requests to the targeted system. A successful exploit could allow the attacker to cause the affected system to become unresponsive, resulting in a DoS condition and preventing the management of dependent devices.

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

A vulnerability in the licensing service of Cisco Firepower Management Center allows unauthenticated remote attackers to send malicious requests that exploit improper handling of system resource values, causing the system to become unresponsive and preventing management of dependent devices.

MitigationApply the latest Cisco FMC software update from Cisco's security advisories to address the improper system resource handling in the licensing service.

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
Secure Firewall Management CenterApplication
Affected:= 6.2.3= 6.3.0= 6.4.0= 6.5.0

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
None
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

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 Cisco FMC product version
    Access the Cisco Firepower Management Center web UI and navigate to System > Licensing, or use the CLI and run 'show version' to display the installed software version
    Affected if The displayed version matches exactly 6.2.3, 6.3.0, 6.4.0, or 6.5.0
  2. Confirm licensing service is active
    In the FMC web UI, verify the Licensing page is accessible and the licensing service is running. From CLI, check process status for 'ftd' or 'sfmgr' related to licensing
    Affected if The licensing service is enabled and responding to requests
  3. Check system responsiveness
    Attempt to access the FMC web UI, log in, and navigate to the Device Management page. Note if the interface is slow to load or times out
    Affected if The FMC interface is unresponsive or significantly slower than normal, or management of dependent devices fails
  4. Review system resource utilization
    From the FMC CLI, run commands such as 'show cpu' or 'show memory' to check system resource usage, or access the System > Health monitor in the web UI
    Affected if System resources appear depleted or the health monitor shows licensing service consuming excessive resources
  5. Audit network exposure
    Review firewall or network access lists to determine if the FMC management interface (port 443) is exposed to untrusted networks
    Affected if The FMC management interface is accessible from untrusted or external networks

You are affected if your Cisco Secure Firewall Management Center runs version 6.2.3, 6.3.0, 6.4.0, or 6.5.0 and the licensing service is exposed to network requests.

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

Apply the latest Cisco FMC software update from Cisco's security advisories to address the improper system resource handling in the licensing service.

Fix this in Secure Firewall Management Center Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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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-2020-3499 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