CVE-2026-107383: MariaDB Connector/Node.js exposes uninitialized process memory through malformed GeoJSON parameters

When encoding a GeoJSON Polygon or MultiPolygon parameter for the binary protocol, the connector sized its output buffer from the length property of each ring, then wrote each ring only if it was a real array. The two loops disagreed: any non-array ring carrying a numeric length (a string, or an object such as {“length”: 4000}) still reserved 4 + 16 * length bytes, but wrote none of them. The buffer came from Buffer.allocUnsafe() and was returned in full regardless of how far the write position had advanced, so every reserved-but-unwritten byte was uninitialized Node.js heap.

The sibling LineString case handled this correctly, aborting with null on the first malformed point, so no reserved byte could escape unwritten.

The only gate on this path is value.type naming a GeoJSON type, so any object shaped like {“type”: “Polygon”, …} reached the encoder.