7.4
HIGH CVSS 3.1
CVE-2026-103921
GraphQL Tools: TLS Certificate Validation Disabled in Legacy GraphQL WebSocket Executor
Description

GraphQL Tools provides utilities for building, stitching, and mocking GraphQL schemas. Prior to 1.1.35, the executor-legacy-ws buildWSLegacyExecutor() function hardcodes TLS certificate rejection off for Node.js connections to wss:// endpoints. Applications using the executor directly, or url-loader with SubscriptionProtocol.LEGACY_WS, can therefore accept an attacker-controlled certificate when a network-positioned attacker intercepts the connection. Authentication material in connectionParams or headers can be disclosed, and subscription data can be modified. Browser WebSocket clients are unaffected because browsers enforce certificate validation. This issue is fixed in version 1.1.35.

INFO

Published Date :

Oct. 1, 2026, 5:17 p.m.

Last Modified :

Oct. 1, 2026, 7:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-103921 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH MITRE-CVE
CVSS 3.1 HIGH [email protected]
Solution
Update GraphQL Tools to 1.1.35 to enforce TLS certificate validation.
  • Update GraphQL Tools to version 1.1.35 or later.
  • Ensure TLS certificate validation is enabled for WebSocket connections.
  • Review and configure connection parameters securely.
  • Monitor network traffic for suspicious activity.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-103921 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-103921 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-103921 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-103921 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 01, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-103921', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-10-01T18:04:13.318417Z'}
  • New CVE Received by [email protected]

    Oct. 01, 2026

    Action Type Old Value New Value
    Added Description GraphQL Tools provides utilities for building, stitching, and mocking GraphQL schemas. Prior to 1.1.35, the executor-legacy-ws buildWSLegacyExecutor() function hardcodes TLS certificate rejection off for Node.js connections to wss:// endpoints. Applications using the executor directly, or url-loader with SubscriptionProtocol.LEGACY_WS, can therefore accept an attacker-controlled certificate when a network-positioned attacker intercepts the connection. Authentication material in connectionParams or headers can be disclosed, and subscription data can be modified. Browser WebSocket clients are unaffected because browsers enforce certificate validation. This issue is fixed in version 1.1.35.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
    Added CWE CWE-295
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/103xxx/CVE-2026-103921.json">CVE-2026-103921</a>
    Added Reference https://github.com/ardatan/graphql-tools/commit/3831a0661514c91d99971052f983552556880402
    Added Reference https://github.com/ardatan/graphql-tools/pull/8426
    Added Reference https://github.com/ardatan/graphql-tools/releases/tag/@graphql-tools/[email protected]
    Added Reference https://github.com/ardatan/graphql-tools/security/advisories/GHSA-6fw5-9hq8-w87g
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.