modelcontextprotocol MCP TypeScript SDK up to 1.30.x/2.1.x OAuth Client improper authorization

Summaryinfo

A vulnerability, which was classified as problematic, has been found in modelcontextprotocol MCP TypeScript SDK up to 1.30.x/2.1.x. Impacted is an unknown function of the component OAuth Client. This manipulation causes improper authorization. This vulnerability is handled as CVE-2026-104850. The attack can be initiated remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in modelcontextprotocol MCP TypeScript SDK up to 1.30.x/2.1.x. It has been declared as problematic. Affected by this vulnerability is an unknown functionality of the component OAuth Client. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality.

This vulnerability is known as CVE-2026-104850. 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. The attack technique deployed by this issue is T1548.002 according to MITRE ATT&CK.

Upgrading to version 1.31.0 or 2.2.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• modelcontextprotocol

Name

• MCP TypeScript SDK

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29
• 1.30
• 2.0
• 2.1

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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