Big Ip Access Policy ManagerApplication · F5
CVE-2020-27716
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 · uneditedOn versions 15.1.0-15.1.0.5, 14.1.0-14.1.3, 13.1.0-13.1.3.5, 12.1.0-12.1.5.2, and 11.6.1-11.6.5.2, when a BIG-IP APM virtual server processes traffic of an undisclosed nature, the Traffic Management Microkernel (TMM) stops responding and restarts.
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 denial of service vulnerability in F5 BIG-IP APM allows an attacker to cause the Traffic Management Microkernel (TMM) to become unresponsive and restart by sending specially crafted traffic to an affected APM virtual server. The specific traffic characteristics that trigger this condition are undisclosed.
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
Big Ip Access Policy ManagerApplication
>= 11.6.1, <= 11.6.5>= 12.1.0, <= 12.1.5>= 13.1.0, <= 13.1.3>= 14.1.0, < 14.1.3.1>= 15.0.0, < 15.1.1CVSS 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 BIG-IP versionRun 'tmsh show /sys version' on the command line, or check System > Software Management in the web UI to view the installed BIG-IP versionAffected if The installed version falls within 11.6.1-11.6.5, 12.1.0-12.1.5, 13.1.0-13.1.3, 14.1.0-14.1.3.0, or 15.1.0-15.1.0.x (prior to fixed releases)
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Verify APM module is provisionedCheck Access Policy Manager provisioning status in the web UI under System > Platform >Provisioning, or run 'tmsh list sys provision apm'Affected if APM shows as provisioned (any level: nominal, minimum, or dedicated)
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Confirm APM virtual servers existReview configured virtual servers in the web UI under Local Traffic > Virtual Servers, or run 'tmsh list ltm virtual' and filter for those with APM policies attachedAffected if Any virtual server has an APM access policy or APM profile assigned
A system is affected if it runs a vulnerable BIG-IP version within the listed ranges AND has APM provisioned AND exposes at least one APM-enabled virtual server to network 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 data14.1.3.115.1.1
Apply the appropriate F5 software update for the affected version (15.1.0.6+, 14.1.3.1+, 13.1.3.6+, 12.1.5.3+, or 11.6.5.3+). If immediate patching is not feasible, consider restricting access to APM virtual servers until the update can be deployed.
Fix this in Big Ip Access Policy Manager
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-27716 — 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-2020-27716 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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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
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