CVE-2026-90474

MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens without providing a client secret or PKCE verifier, gaining access to victim accounts and their privileges.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/samanhappy/mcphub/blob/v1.0.31/src/services/oauthServerService.ts#L26-L38
https://github.com/samanhappy/mcphub/commit/e927620cd1a80e8691213b01eb8cd6ffa1a66e9f
https://github.com/samanhappy/mcphub/releases/tag/v1.0.32
https://github.com/samanhappy/mcphub/security/advisories/GHSA-3m7m-37xf-xp9x
https://www.vulncheck.com/advisories/mcphub-before-1.0.32-oauth-2.0-authentication-bypass
https://github.com/samanhappy/mcphub/security/advisories/GHSA-3m7m-37xf-xp9x

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-12 11:16

Updated : 2026-09-15 17:17

NVD link : CVE-2026-90474

Mitre link : CVE-2026-90474

CVE.ORG link : CVE-2026-90474

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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