fix(geocoder): reject control chars in :id to prevent NUL-byte 500#13
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A NUL byte anywhere in the :id path param passed the PAND / NUMMERAANDUIDING startsWith() branch and reached Postgres as a bind parameter, raising `invalid byte sequence for encoding "UTF8": 0x00`. That error escaped the route handler and surfaced as HTTP 500 instead of a clean 404 — letting a client trivially generate 500s and pollute the error log (no injection risk; queries are parameterized). detectFormat now classifies any input containing a C0 control char or DEL (0x7f) as "unknown", so every product route returns 404. Found via input fuzzing of the live WS (~4.7M requests over 4h; the NUL byte was the only 5xx class observed). Adds 5 regression cases. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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What
A NUL byte (
%00) anywhere in the:idpath parameter caused HTTP 500 instead of a clean 404 on every/v4/product/*route.detectFormatmatched theNL.IMBAG.PAND./NL.IMBAG.NUMMERAANDUIDING.prefix viastartsWith()and passed the NUL-containing id straight into the SQL bind parameter. Postgres rejects it:That error escaped the route handler →
onError→500 {"message":"Internal server error"}. No injection risk (queries are parameterized), but a client could trivially spam 500s and flood the error log.Fix
detectFormatnow classifies any input containing a C0 control character or DEL (0x7f) as"unknown", so the route returns 404. Central guard at the shared classifier — covers analysis / risk / light / statistics in one place.How it was found
Input-fuzzing the live WS — ~4.7M requests over a 4h aggressive run (real-ID corpus + targeted mutators + malformed HTTP). The NUL byte was the only 5xx class observed across the entire run; a Schemathesis property pass found no other server error.
Verification
bun test— 49 pass (5 new regression cases for NUL/tab/DEL).bun run typecheck— clean.🤖 Generated with Claude Code