CVE-2026-40159: PraisonAI is a multi-agent teams system. Prior to 4.5.128, PraisonAI’s MCP (Model Context Protocol) integration allows spawning background servers via stdio…

PriorityP432medium5.5CVSS 3.1

AVLACLPRNUIRSUCHINAN

EPSS

0.18%

8.0th percentile

PraisonAI is a multi-agent teams system. Prior to 4.5.128, PraisonAI’s MCP (Model Context Protocol) integration allows spawning background servers via stdio using user-supplied command strings (e.g., MCP("npx -y @smithery/cli ...")). These commands are executed through Python’s subprocess module. By default, the implementation forwards the entire parent process environment to the spawned subprocess. As a result, any MCP command executed in this manner inherits all environment variables from the host process, including sensitive data such as API keys, authentication tokens, and database credentials. This behavior introduces a security risk when untrusted or third-party commands are used. In common scenarios where MCP tools are invoked via package runners such as npx -y, arbitrary code from external or potentially compromised packages may execute with access to these inherited environment variables. This creates a risk of unintended credential exposure and enables potential supply chain attacks through silent exfiltration of secrets. This vulnerability is fixed in 4.5.128.

Affected

4 ranges

Vendor	Product	Version range	Fixed in
mervinpraison	praisonai	< 4.5.128	4.5.128
mervinpraison	praisonai	>= 0 < 4.6.59	4.6.59
mervinpraison	praisonai	>= 0 < 4.5.128	4.5.128
praison	praisonai	< 4.5.128	4.5.128

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