langbot-app LangBot up to 4.10.7 MCP Server Configuration mcp.py improper authorization

Summaryinfo

A vulnerability, which was classified as critical, was found in langbot-app LangBot up to 4.10.7. This affects an unknown part of the file src/langbot/pkg/provider/tools/loaders/mcp.py of the component MCP Server Configuration. The manipulation results in improper authorization. This vulnerability is known as CVE-2026-54449. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability, which was classified as critical, was found in langbot-app LangBot up to 4.10.7. Affected is some unknown functionality of the file src/langbot/pkg/provider/tools/loaders/mcp.py of the component MCP Server Configuration. The manipulation with an unknown input leads to a improper authorization vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

LangBot is a global IM bot platform designed for LLMs. In version 4.10.7 and earlier, any authenticated user can add or change an STDIO MCP server configuration without an adequate authorization boundary. In src/langbot/pkg/provider/tools/loaders/mcp.py, StdioServerParameters accepts the configured command and arguments and starts a server-side subprocess on the LangBot server. An attacker who can sign up or obtain an account can use the Extensions MCP configuration to execute arbitrary commands with the privileges of the LangBot service, enabling data disclosure, modification, and service disruption. No fixed version is available as of this review.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-54449 since 06/15/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/20/2026). The MITRE ATT&CK project declares the attack technique as T1548.002.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• langbot-app

Name

• LangBot

Version

• 4.10.0
• 4.10.1
• 4.10.2
• 4.10.3
• 4.10.4
• 4.10.5
• 4.10.6
• 4.10.7

Website

• Product: https://github.com/langbot-app/LangBot/

CPE 2.3info

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Once again VulDB remains the best source for vulnerability data.

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