CVE-2020-5420
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 · uneditedCloud Foundry Routing (Gorouter) versions prior to 0.206.0 allow a malicious developer with "cf push" access to cause denial-of-service to the CF cluster by pushing an app that returns specially crafted HTTP responses that crash the Gorouters.
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 confidenceIn Cloud Foundry's Gorouter (routing component) versions before 0.206.0, a malicious developer with 'cf push' permissions can deploy an application that sends specially crafted HTTP responses designed to crash Gorouter processes. Since Gorouter handles all HTTP traffic routing for the CF cluster, crashing these routers causes denial of service for the entire platform.
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< 13.15.0< 0.206.0CVSS 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
- Changed
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/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 checksWork through these to decide whether this CVE applies to you.
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Identify Gorouter versionLocate and inspect the Gorouter component version in your Cloud Foundry deployment (typically via bosh deployments, ops manager, or cf CLI 'cf buildpacks' or 'cf app' routing info)Affected if Gorouter version is below 0.206.0
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Identify Cloud Foundry deployment versionCheck the overall Cloud Foundry Cf Deployment release number (via bosh deployments, ops manager, or cf CLI 'cf curl /v2/info')Affected if Cf Deployment version is below 13.15.0
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Confirm routing component is exposedVerify that Gorouter is actively handling HTTP traffic for the CF cluster by checking router job status in bosh or observing active routes via 'cf routes'Affected if Gorouter is running and routing traffic
Your environment is affected if Gorouter is version 0.206.0 or lower, or if your overall Cf Deployment is 13.15.0 or lower, and Gorouter is actively routing HTTP 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 data0.206.013.15.0
Upgrade Gorouter to version 0.206.0 or later. Additionally, review and restrict 'cf push' access to only trusted developers using least-privilege principles, as this attack requires an authenticated developer with application deployment permissions.
- Consultation3.0 h
- Implementation6.0 h
- Testing3.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-5420 — 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-2020-5420 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
- No weaponised exploit code, or anything meant to cause harm
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