dbcve.org
Adaptive Security Appliance SoftwareOperating system · Cisco

CVE-2020-3334

HIGH · 7.4 CVSS v3.1 Published 2020-05-06
Fix available
A fix is available. Upgrade to 6.6.0 / 9.10.1.37 or later.
See remediation →
79/100
Remediation priority · High
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 ARP packet processing of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Security Appliances could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect processing of ARP packets received by the management interface of an affected device. An attacker could exploit this vulnerability by sending a series of unicast ARP packets in a short timeframe that would reach the management interface of an affected device. A successful exploit could allow the attacker to consume resources on an affected device, which would prevent the device from sending internal system keepalives and eventually cause the device to reload, resulting in a denial of service (DoS) condition.

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 ARP packet processing on the management interface of Cisco ASA and FTD Software for Firepower 2100 Series allows an adjacent, unauthenticated attacker to send malicious unicast ARP packets that exhaust device resources, preventing internal keepalives and causing the device to reload, resulting in denial of service.

MitigationApply the Cisco software update that corrects ARP packet handling on the management interface. If no patch is available, restrict physical/logical access to the management network segment to prevent adjacent attacks.

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
Adaptive Security Appliance SoftwareOperating system
Affected:>= 9.10, < 9.10.1.37>= 9.12, < 9.12.3>= 9.13, < 9.13.1.2
Secure Firewall Threat DefenseApplication
Affected:< 6.6.0

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
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:A/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 device model
    Run 'show version' or check hardware inventory to confirm the device is a Firepower 2100 Series appliance
    Affected if Device model is Firepower 2100 Series (the only affected hardware platform)
  2. Identify software type
    Run 'show version' to determine if the device runs Cisco ASA Software or Cisco Firepower Threat Defense (FTD)
    Affected if Software is either ASA or FTD (only these products are affected)
  3. Check ASA version
    If running ASA, run 'show version' and locate the running software version (e.g., 9.12.1). Compare against affected ranges: >= 9.10 but < 9.10.1.37; >= 9.12 but < 9.12.3; >= 9.13 but < 9.13.1.2
    Affected if ASA version falls within any of the affected version ranges
  4. Check FTD version
    If running FTD, run 'show version' or check the FTD software version. Compare against affected range: < 6.6.0
    Affected if FTD version is below 6.6.0
  5. Verify management interface status
    Run 'show interface' or 'show ip address' to confirm the management interface (typically Management0/0) is configured and active
    Affected if Management interface is configured and reachable (exploit requires sending ARP packets to the management interface)

The device is affected if it is a Firepower 2100 Series running ASA in versions 9.10.x before 9.10.1.37, 9.12.x before 9.12.3, or 9.13.x before 9.13.1.2; or running FTD version below 6.6.0, and the management interface is configured and accessible on a network segment.

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
Upgrade available Upgrade to 6.6.0 / 9.10.1.37 / 9.12.3 or later
Fixed in 6.6.09.10.1.379.12.3
Interim mitigation

Apply the Cisco software update that corrects ARP packet handling on the management interface. If no patch is available, restrict physical/logical access to the management network segment to prevent adjacent attacks.

Fix this in Adaptive Security Appliance Software Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,130
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,408.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-3334 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2020-3334 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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