Accepted a protocol violation and carried on. The anomaly was on the control stream, and this client extended flow-control credit on it -- a receiver extends credit on a stream only once its application has consumed what was already there, so the bytes were read rather than merely delivered. This should have been rejected.
The client did something the clause forbids, or failed to do what it requires.
What was measured
- Client
- msquic — .NET HttpClient + msquic, 2.7.0 (7e6525d)
- Test
- Control stream whose first frame is not SETTINGS —
h-missing-settings - Clause
- RFC 9114 §6.2.1 (MUST)
- Class
- correctness — Rejected something invalid, with the code the RFC names.
- Required behaviour
- Close the connection with H3_MISSING_SETTINGS.
- Measured
- 2026-10-27
Reproduce it
The suite is the judge, so the reproduction is to point the same client at the same test and let the server report what it saw.
SESSION=$(curl -sX POST https://conformance.pqcrypta.com/session | jq -r .id)
# then drive msquic at the test URL and read the verdict:
curl -s https://conformance.pqcrypta.com/report/$SESSION.json | jq '.results["h-missing-settings"]'