CVE-2026-118666

The @graphql-tools/executor-legacy-ws package (prior to version 1.1.36 ) contains a cross-tenant data leak vulnerability in the buildWSLegacyExecutor component. The root cause is twofold: the executor reuses a single WebSocket and overwrites the websocket.onmessage handler on every new subscripti...

CVE-2026-118666 GraphQL Tools: Shared legacy executor routes one subscription's results to a different caller

GraphQL Tools provides utilities for building, stitching, and mocking GraphQL schemas. Prior to version 1.1.36 of the GraphQL Tools legacy WebSocket executor package, buildWSLegacyExecutor in packages/executors/legacy-ws/src/index.ts reuses one WebSocket and replaces its single websocket.onmessag...