CVE-2020-5402
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 · uneditedIn Cloud Foundry UAA, versions prior to 74.14.0, a CSRF vulnerability exists due to the OAuth2 state parameter not being checked in the callback function when authenticating with external identity providers.
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 confidenceThis is a CSRF vulnerability in Cloud Foundry UAA where the OAuth2 state parameter is not validated in the callback function during external identity provider authentication. An attacker could craft malicious links to hijack the OAuth2 flow and potentially gain unauthorized access to user accounts by tricking victims into initiating authentication that gets redirected through the attacker's controlled endpoint.
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< 12.33.0< 74.14.0CVSS 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
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/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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Check UAA versionDetermine the installed version of Cloud Foundry User Account and Authentication (UAA) by accessing the UAA admin console or running 'uaac version' or checking the deployment manifest. Compare this version number against the affected range: versions prior to 74.14.0Affected if The installed UAA version is 74.13.0 or earlier, or the UAA component version is less than 74.14.0
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Check Cloud Foundry deployment versionIf using full CF Deployment, check the deployment version by inspecting the deployment manifest or using the cf CLI 'cf version' and checking the CF Deployment release version. Compare against affected range: versions prior to 12.33.0Affected if The CF Deployment version is 12.32.0 or earlier, or the deployment includes UAA components older than 74.14.0
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Identify external identity provider configurationExamine the UAA configuration to determine if any external identity providers (such as SAML or OIDC providers like Okta, Azure AD, or Google) are configured for user authentication. This is typically found in the UAA databaseuaa database or the SAML configuration XML filesAffected if External identity providers are configured and enabled for authentication - this is the required condition for the OAuth2 state parameter vulnerability to be exploitable
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Verify OAuth2 state parameter handlingReview UAA logs or configuration for the OAuth2 callback endpoint handling. Check if the 'state' parameter is being validated during the OAuth2 authorization callback from external identity providers. This typically involves inspecting the UAA source code or configuration related to OAuth2 callback processingAffected if The OAuth2 callback handler does not validate or reject invalid/missing state parameters - the callback accepts any state value without validation
You are affected if your UAA version is below 74.14.0 (or CF Deployment below 12.33.0) AND you have external identity providers configured for authentication, since the state parameter validation is missing in the OAuth2 callback flow.
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 data12.33.074.14.0
Upgrade UAA to version 74.14.0 or later which implements proper state parameter validation in the OAuth2 callback handler.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA3.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2020-5402 — 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-2020-5402 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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