VDB-349591 · CVE-2026-30241 · GHSA-m4h2-mjfm-mp55

mercurius-js mercurius up to 16.7.x GraphQL Subscription authorization

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7.2	$0-$5k	0.00

Summaryinfo

A vulnerability marked as critical has been reported in mercurius-js mercurius up to 16.7.x. Affected by this vulnerability is an unknown functionality of the component GraphQL Subscription Handler. This manipulation causes authorization. This vulnerability is handled as CVE-2026-30241. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in mercurius-js mercurius up to 16.7.x and classified as critical. Affected by this vulnerability is an unknown code of the component GraphQL Subscription Handler. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-863. The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions. As an impact it is known to affect integrity, and availability. The summary by CVE is:

Mercurius is a GraphQL adapter for Fastify. Prior to version 16.8.0, Mercurius fails to enforce the configured queryDepth limit on GraphQL subscription queries received over WebSocket connections. The depth check is correctly applied to HTTP queries and mutations, but subscription queries are parsed and executed without invoking the depth validation. This allows a remote client to submit arbitrarily deeply nested subscription queries over WebSocket, bypassing the intended depth restriction. On schemas with recursive types, this can lead to denial of service through exponential data resolution on each subscription event. This issue has been patched in version 16.8.0.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-30241 since 03/04/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 16.8.0 eliminates this vulnerability. Applying the patch 5b56f60f4b0d60780b0ff499a479bd830bdd6986 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

mercurius-js

Name

mercurius

Version

License

open-source

Website

Product: https://github.com/mercurius-js/mercurius/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.2
NVD Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-863 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: mercurius 16.8.0
Patch: 5b56f60f4b0d60780b0ff499a479bd830bdd6986

Timelineinfo

03/04/2026 CVE reserved
03/07/2026 +3 days Advisory disclosed
03/07/2026 +0 days VulDB entry created
03/12/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-m4h2-mjfm-mp55
Status: Confirmed

CVE: CVE-2026-30241 (🔒)
GCVE (CVE): GCVE-0-2026-30241
GCVE (VulDB): GCVE-100-349591

Entryinfo

Created: 03/07/2026 09:02
Updated: 03/12/2026 16:36
Changes: 03/07/2026 09:02 (70), 03/08/2026 11:37 (1), 03/12/2026 16:36 (12)
Complete: 🔍
Cache ID: 216:F9C:103