CVE-2021-20393
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 · uneditedIBM QRadar User Behavior Analytics 1.0.0 through 4.1.0 could allow a remote attacker to obtain sensitive information when a detailed technical error message is returned in the browser. This information could be used in further attacks against the system. IBM X-Force ID: 196001.
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 confidenceIBM QRadar UBA versions 1.0.0 through 4.1.0 returns detailed technical error messages (potentially including stack traces, file paths, version info, or configuration details) directly to the browser. A remote unauthenticated attacker can trigger these errors to gather sensitive system information useful for planning further 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>= 1.0.0, < 4.1.1CVSS 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
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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 installed QRadar UBA versionLocate the version information for IBM QRadar UBA in the administrative console or by querying the system configuration files. Common locations include the product UI header, About section, or version logs.Affected if The installed version is 1.0.0 through 4.1.0 inclusive (anything below 4.1.1 within the 1.x-4.x range).
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Trigger an error conditionSend a malformed request or invalid input to the QRadar UBA web interface to provoke an error response. This could include invalid parameters, missing required fields, or requests to non-existent resources.Affected if The HTTP response contains detailed technical information such as stack traces, file paths, Java class names, version numbers, or configuration details rather than a generic error message.
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Inspect HTTP response headers and bodyExamine the complete HTTP response from the web application when an error occurs. Look for headers like X-Stack-Trace, X-Exception, or similar debug headers, and check the response body for verbose error content.Affected if The response exposes technical implementation details including server technology, framework versions, or internal system paths.
You are affected if the installed QRadar UBA version is between 1.0.0 and 4.1.0 AND triggering an error returns detailed technical information instead of generic messages.
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 data4.1.1
Configure the application to display generic error messages to end users rather than detailed technical information. Implement custom error pages and ensure verbose exception handling is disabled in production. Review and patch to a version beyond 4.1.0 if available.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 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 $3,088.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-20393 — 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-2021-20393 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
- No spam, self-promotion, credentials, or personal data