CVE-2021-33831
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 · uneditedapi/account/register in the TH Wildau COVID-19 Contact Tracing application through 2021-09-01 has Incorrect Access Control. An attacker can interfere with tracing of infection chains by creating 500 random users within 2500 seconds.
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 confidenceThe api/account/register endpoint in the TH Wildau COVID-19 Contact Tracing application lacks proper access controls, allowing unauthenticated attackers to programmatically create fake user accounts. An attacker can register 500 random users within approximately 41 minutes (2500 seconds), degrading the system's ability to accurately track infection chains through noise and fake data.
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<= 2021-09-01CVSS 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
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/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 if TH Wildau COVID-19 Contact Tracing application is deployedInventory your web applications and APIs to determine if the TH Wildau COVID-19 Contact Tracing system is present in your environmentAffected if The application is found in your environment and no additional authentication is required to access the registration endpoint
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Determine the installed versionCheck the application version or build metadata against the affected range (<= 2021-09-01). This may be visible in application headers, a version endpoint, or the software buildAffected if The installed version is <= 2021-09-01 or the version cannot be determined
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Verify the registration endpoint is accessible without authenticationSend a POST request to /api/account/register without providing any authentication credentials and observe if the request succeedsAffected if The endpoint returns a successful account creation response (HTTP 200 or 201) without requiring authentication tokens or session cookies
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Check if rate limiting is enforced on the registration endpointSend multiple rapid registration requests (for example, 10-20 requests in quick succession) and examine if the application throttles or blocks excessive requestsAffected if No rate limiting is detected - all requests are processed without HTTP 429 responses or request blocking
A user is affected if the TH Wildau COVID-19 Contact Tracing application (version <= 2021-09-01) is deployed and the /api/account/register endpoint accepts unauthenticated requests without rate limiting protection.
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 dataImplement authentication requirements for the registration endpoint and add rate limiting to prevent automated mass account creation. Consider requiring admin approval or CAPTCHA for new registrations.
- 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-2021-33831 — 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-2021-33831 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