CVE-2026-118666
Published:October 28, 2026
Updated:October 29, 2026
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.
Affected Packages
https://github.com/ardatan/graphql-tools.git (GITHUB):
Affected version(s) >=@graphql-tools/executor-legacy-ws@1.0.1 <@graphql-tools/executor-legacy-ws@1.1.36Fix Suggestion:
Update to version @graphql-tools/executor-legacy-ws@1.1.36@graphql-tools/executor-legacy-ws (NPM):
Affected version(s) >=1.0.1-rc-20230612102029-16c7ce78 <1.1.36Fix Suggestion:
Update to version 1.1.36Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
6
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
PRESENT
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.9
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
LOW
Weakness Type (CWE)
Exposure of Sensitive Information to an Unauthorized Actor