Adaptive Security ApplianceApplication · Cisco
CVE-2020-3554
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 · uneditedA vulnerability in the TCP packet processing of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a memory exhaustion condition. An attacker could exploit this vulnerability by sending a high rate of crafted TCP traffic through an affected device. A successful exploit could allow the attacker to exhaust device resources, resulting in a DoS condition for traffic transiting the affected device.
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 confidenceA memory exhaustion vulnerability in the TCP packet processing of Cisco ASA and FTD software allows an unauthenticated remote attacker to send crafted TCP traffic at a high rate, exhausting device resources and causing a denial of service for all transiting traffic.
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 ApplianceApplication
< 9.12.4.3
Secure Firewall Threat DefenseApplication
<= 6.2.2>= 6.3.0, < 6.4.0.10>= 6.5.0, < 6.5.0.5= 6.6.0
Adaptive Security Appliance SoftwareOperating system
>= 9.13.0, < 9.13.1.13>= 9.14.0, < 9.14.1.30CVSS 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
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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 checksWork through these to decide whether this CVE applies to you.
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Identify device type and software platformLog into the device CLI and run 'show version' or 'show inventory' to determine if the device is running Cisco ASA or Firepower Threat Defense (FTD) softwareAffected if The device is running Cisco ASA or FTD software
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Determine installed ASA software versionRun 'show version' command and locate the ASA software version number (example format: 9.12.x.x)Affected if ASA version is < 9.12.4.3 OR >= 9.13.0 and < 9.13.1.13 OR >= 9.14.0 and < 9.14.1.30
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Determine installed FTD software versionRun 'show version' command and locate the FTD software version numberAffected if FTD version is <= 6.2.2 OR >= 6.3.0 and < 6.4.0.10 OR >= 6.5.0 and < 6.5.0.5 OR = 6.6.0
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Confirm TCP processing is activeVerify the device has active TCP traffic handling by checking interface status with 'show interface' or checking that security policies are appliedAffected if The device is actively processing TCP traffic (this is the default operational state)
The device is affected if it runs Cisco ASA or FTD software with a version number that falls within any of the listed vulnerable ranges and is processing TCP traffic.
Generated from the published advisory. Verify against your own configuration.
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 data6.4.0.106.5.0.59.12.4.3
Apply the relevant Cisco security update for ASA/FTD software to patch the memory exhaustion vulnerability in TCP packet processing.
Fix this in Adaptive Security Appliance
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,808.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-3554 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2020-3554 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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