Microsoft Security Response Center (MSRC) vs Mozilla http scanner

MSRC's CVRF API serves Microsoft's own machine-readable security-update bulletins: list every bulletin's ID and dates from `/updates`, then pull one full document by ID (e.g. "2026-Jan") from `/cvrf/{id}` -- as CVRF XML by default, or the same CVRF document serialised to JSON under an `Accept: application/json` header. It's a fully public, unauthenticated REST endpoint with no signup or key required, backing tools like the community MsrcSecurityUpdates PowerShell module. Two traps confirmed live: the OData-shaped response envelope is misleading (most `$filter`/`$top` syntax 500s, and there's no CVE-to-bulletin lookup at all), and the separately documented `/csaf/{id}` route rejected all 17 id formats probed with "Invalid ID format" -- so despite the CSAF branding, the JSON this API actually returns is CVRF, not CSAF. The old stored URL pointed at the unrelated Report Abuse API's developer page; the live developer portal for this security-updates API now redirects straight to its published OpenAPI/Swagger definition.

The HTTP Observatory grades a website's security headers -- CSP, HSTS, cookie flags, and more -- against Mozilla's recommended baseline, the same engine behind the long-running Mozilla Observatory scanner. The original mozilla/http-observatory Python API was shut down on 2024-10-31 when the tool moved to MDN; automated callers now POST to a v2 scan endpoint that returns a grade, score, and pass/fail counts, with a details link back to the full MDN report. It's fully public and keyless, rate-limited to one fresh scan per host per minute (cached results are returned for repeat calls within that window), and built for CI-pipeline use.