0:00The diff that 'works'A Next.js DELETE handler reads an id from JSON, concatenates it into SQL, and returns a live-looking secret key in the response.
0:08What it should catchA secret in source. SQL built with string concatenation. No check that this caller owns the note. The key echoed back to the client.
0:16Severity, then the fixHigh: move the key to an environment variable and rotate it. High: parameterize the query. High: derive the user from the session and filter the delete by owner.
0:24What it will not doIt will not hand you a working exploit. The sample key is fake. The output is the safer handler, not a payload.
No daily video for this drop yet. The in and out lines above are the preview.
0:08What actually shippedLogin on staging, pricing table render, stripe package installed. Plan change is still a stub. PayPal left alone on purpose.
0:16What is brokenWebhook 400, missing signature check, BillingForm customerId null, receipt email not wired. Ranked by what blocks the rest.
0:24Tomorrow's first promptA paste-ready prompt that starts at the webhook 400, forbids touching PayPal, and asks for a signature check plus a failing test.
No daily video for this drop yet. The in and out lines above are the preview.
0:00The sampleevt_1844, type refund.requested, order 1844, amount 40. Signature header documented as HMAC-SHA256 of the raw body. Retries for 24 hours.
0:08Requiredid, type, data.order_id, data.amount, data.currency. created is optional for the side effect.
0:16IdempotencyStore evt_1844. A second delivery with the same id returns 200 and does not refund again.
0:24The checkCompute HMAC-SHA256 over the raw body with the stored secret and compare to X-Signature. Mismatch is 401 and no side effect. No bypass is described.
No daily video for this drop yet. The in and out lines above are the preview.
Questions
What are the alternatives to Env Var Auditor?
gitleaks or GitHub secret scanning (dedicated tool); grep for process.env (by hand). On One Agent a Day, Vibe-code Security Checker, Diff Risk Reviewer, Session Handoff, Webhook Contract Writer do a similar job.
When is gitleaks or GitHub secret scanning better than Env Var Auditor?
Gitleaks or GitHub secret scanning is the better pick when you need to scan a whole repo and its history for leaked secrets. Env Var Auditor is the better pick when you need the example file and the code reconciled so the app boots on a fresh machine.
When is grep for process.env better than Env Var Auditor?
Grep for process.env is the better pick when the project is small and you know the code. Env Var Auditor is the better pick when the model added keys in five files and you want the diff explained in one list.
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