Unauthenticated Warranty Claim Submission Creates Real CRM Cases in Production
The Risk
A national postal carrier's online warranty claim form accepted submissions from anyone on the internet, with no login and no checks that the person actually had an account. A single web request created a real case in the company's customer support system against any tracking number. An attacker could flood the claims team with thousands of fake cases or quietly file fraudulent claims hoping for payouts. Staff would have to review and close each case by hand.
The Vulnerability
The transit warranty claim workflow on a national postal carrier's logistics portal had two compounding flaws that let any anonymous internet user file claims directly into the production support system.
Flaw 1: Eligibility screening enforced only in the browser
The eligibility page presented radio-button questions ("Is your shipment within the warranty period?", "Do you have proof of value?"). The answers were checked entirely by JavaScript in the user's browser. The server never validated them. Sending a single POST with a specific event target value was enough to bypass the screening and obtain a session for the claim form, even though no questions had been answered.
Flaw 2: No authentication on claim submission
The claim form processed submissions from unauthenticated users. The server's own response body confirmed this with loginStatus = 'Anonymous'. Account numbers entered on the form were not validated against any account database. All input validators were client-side only. Submitting the form created a real case in the production CRM and emailed a confirmation to whatever address was supplied.
The Attack
The attack required only curl and three HTTP requests.
- GET the screening page to obtain anti-forgery tokens. Server returned HTTP 200 with
loginStatus = 'Anonymous'embedded in the page. - POST back to the same page with the captured tokens and a single event target parameter pointing to the "Complete Claim Online" postback. No radio-button values needed. Server responded HTTP 302 redirecting to the claim form.
- GET the claim form. Server returned HTTP 200 and the same anonymous session was carried through.
- POST the populated claim form. Server created a real CRM case and returned the case number in the response.
Confirmed bypasses
| Control | Expected | Actual |
|---|---|---|
| Eligibility screening | Server validates answers | Bypassed with one event target POST |
| Authentication | Logged-in account required | Anonymous session accepted |
| Account ownership | Account number verified | Fake account number accepted |
| File attachments | Required (browser side) | Not enforced server-side |
| Rate limiting | Throttled | 10 rapid sequential bypass POSTs all returned 302 |
A single end-to-end test produced a live case number in the production CRM. The response body returned the case identifier and confirmed the submission had been raised.
The Impact
Any person on the internet, with no account and no relationship to the carrier, could file transit warranty claims in the production CRM. Fraudulent claims could be filed against any real consignment number because account ownership was never verified.
Operational disruption
With no rate limiting in place, automated mass submission of fake cases is straightforward. Each fake case must be triaged and closed by a human claims handler. A single attacker could overwhelm the claims processing team and slow legitimate refunds for real customers.
Direct financial exposure
The transit warranty process can result in financial payouts when claims are approved. Without server-side account verification, fraudulent claims submitted against real consignment numbers could reach approvers. Whether payment goes through then depends entirely on claim handler diligence rather than any technical control.
Reputational damage
Confirmation emails from the official carrier domain were sent to whatever address an attacker supplied. The same channel can be abused to send phishing-grade messages from a trusted sender to arbitrary recipients.
Remediation
- Require authentication on the claim form and tie submissions to the logged-in account
- Validate eligibility answers and account numbers server-side, not in browser JavaScript
- Verify that the supplied account number is owned by the authenticated user, and that the consignment number belongs to that account
- Add per-IP and per-account rate limits on claim submissions
- Add CAPTCHA or equivalent challenge on the public-facing entry point until the user has authenticated
- Audit the existing CRM for claims submitted with anonymous sessions and flag them for manual review