{"schema":"threatline.record/2","record":{"id":"CVE-2026-103921","aliases":["GHSA-6fw5-9hq8-w87g"],"summary":"GraphQL Tools: TLS Certificate Validation Disabled in Legacy GraphQL WebSocket Executor","details":"## Impact\n\n`buildWSLegacyExecutor()` in `@graphql-tools/executor-legacy-ws` previously hardcoded `rejectUnauthorized: false` when creating WebSocket connections over WSS. This disabled TLS certificate validation, allowing a network-positioned attacker to perform a Man-in-the-Middle (MITM) attack against applications that use this executor with a `wss://` endpoint. Credentials passed via `connectionParams` or `headers` could be intercepted, and subscription data could be tampered with.\n\n**Who is impacted:** Applications using `@graphql-tools/executor-legacy-ws` (directly or via `@graphql-tools/url-loader` with `SubscriptionProtocol.LEGACY_WS`) to connect to a `wss://` endpoint from Node.js while sending authentication material over the connection.\n\nBrowser WebSocket clients are unaffected by this option (browsers always validate certificates).\n\n## Patches\n\nUpgrade to `@graphql-tools/executor-legacy-ws@1.1.35` or later (and `@graphql-tools/url-loader@9.1.9` or later if you use the loader). TLS certificate validation is enabled by default. Callers that intentionally use self-signed certificates in trusted environments can opt out with `rejectUnauthorized: false`.\n\n## Workarounds\n\n- Prefer the modern `graphql-ws` / `SubscriptionProtocol.WS` path where possible.\n- Until upgraded, avoid sending secrets over legacy WSS connections, or terminate TLS at a trusted proxy and use `ws://` only on trusted networks.\n- Supply a custom `webSocketImpl` that enforces certificate validation.","categories":["Libraries & packages"],"product":"@graphql-tools/executor-legacy-ws","vendor":"ardatan","ecosystem":"npm","affected_ranges":[{"source":"GitHub Advisory Database","source_url":"https://github.com/advisories/GHSA-6fw5-9hq8-w87g","source_modified_at":"2026-10-05T22:56:58Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"@graphql-tools/executor-legacy-ws"},"range":"<= 1.1.34"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-103921","source_modified_at":"2026-10-01T18:04:28.083Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"graphql-tools","vendor":"ardatan","versions":[{"version":"< 1.1.35","status":"affected"}],"defaultStatus":null},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-103921","source_modified_at":"2026-10-01T18:04:28.083Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"executor-legacy-ws","vendor":"@graphql-tools","versions":[{"version":"< 1.1.35","status":"affected"}],"defaultStatus":null},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-6fw5-9hq8-w87g","source_modified_at":"2026-10-05T23:15:03.996305160Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"@graphql-tools/executor-legacy-ws","purl":"pkg:npm/%40graphql-tools/executor-legacy-ws"},"ranges":[{"events":[{"introduced":"0"},{"fixed":"1.1.35"}],"type":"SEMVER"}],"versions":[]}],"fixed_versions":[{"source":"GitHub Advisory Database","source_url":"https://github.com/advisories/GHSA-6fw5-9hq8-w87g","source_modified_at":"2026-10-05T22:56:58Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"@graphql-tools/executor-legacy-ws"},"version":"1.1.35"},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-6fw5-9hq8-w87g","source_modified_at":"2026-10-05T23:15:03.996305160Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"@graphql-tools/executor-legacy-ws","purl":"pkg:npm/%40graphql-tools/executor-legacy-ws"},"version":"1.1.35"}],"cvss":7.4,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00268,"percentile":0.17942,"score_date":"2026-10-23"},"published_at":"2026-10-01T16:32:37.865Z","modified_at":"2026-10-05T23:15:03.996305160Z","provenance":[{"source":"GitHub Advisory Database","url":"https://github.com/advisories/GHSA-6fw5-9hq8-w87g","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-05T22:56:58Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-103921","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-01T18:04:28.083Z"},{"source":"OSV","url":"https://osv.dev/vulnerability/GHSA-6fw5-9hq8-w87g","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-05T23:15:03.996305160Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-103921","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["GitHub Advisory Database","CVE List","OSV","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/ardatan/graphql-tools/security/advisories/GHSA-6fw5-9hq8-w87g","tags":["x_refsource_CONFIRM"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-103921","source":"GitHub Advisory Database"},{"source":"CVE List","url":"https://github.com/ardatan/graphql-tools/pull/8426","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/ardatan/graphql-tools/commit/3831a0661514c91d99971052f983552556880402","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/ardatan/graphql-tools/releases/tag/@graphql-tools/executor-legacy-ws@1.1.35","tags":["x_refsource_MISC"]},{"url":"https://github.com/advisories/GHSA-6fw5-9hq8-w87g","source":"GitHub Advisory Database"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","ssvc":{"exploitation":"none","automatable":"no","technical_impact":"total","assessed_at":"2026-10-01T18:04:13.318417Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"ecosystem","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-05T23:15:03.996305160Z","content_hash":"75c27ed286080d56bc29e3746bbcb9c295180c5713fb9655bacb3fc3be4f3ad2"}}