Medium 6.0Published Oct 28, 2026

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

Updated under an hour ago (Oct 29, 2026, 9:40 AM ET)

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It affects ardatan graphql-tools and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for ardatan graphql-tools

Exploited in the last 30 days

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.onmessage handler whenever a new overlapping subscription starts. The handler delivers LEGACY_WS.DATA frames to the newest observer without comparing data.id with the subscription operation id, so a caller using the same executor can receive another user's authorized subscription payload while the earlier caller's stream is starved. This issue is fixed in version 1.1.36 of the GraphQL Tools legacy WebSocket executor package.

CVSS: 6.0 MEDIUM (v4.0, CNA)CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N
Weakness (CWE): CWE-200
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Received
Record last updated: Oct 28, 2026
First seen by InfoSec Signals: Oct 28, 2026

Affected products

Affected products

ardatan graphql-tools ardatan:graphql_tools (from the name)	before 9.0.36	CNA record
@graphql-tools executor-legacy-ws graphql_tools:executor_legacy_ws (from the name)	before 1.1.36	CNA record

References

References

https://github.com/ardatan/graphql-tools/security/advisories/GHSA-mp66-8ww2-pcwm	x-refsource-confirm
https://github.com/ardatan/graphql-tools/pull/8480	x-refsource-misc
https://github.com/ardatan/graphql-tools/commit/c2f226e6f68236be9e4a577f29faeaa92547458b	x-refsource-misc
https://github.com/ardatan/graphql-tools/releases/tag/@graphql-tools/executor-legacy-ws@1.1.36	x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.