Information disclosure in Mervinpraison Praisonai
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 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.
Vulnerability class: Information Disclosure
EPSS: 0.002 (7.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.
Affected products
- Mervinpraison Praisonai — versions < 4.5.128
- Praison Praisonai
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-40159?
- CVE-2026-40159 is a medium-severity vulnerability in Mervinpraison Praisonai, classified under Information Disclosure. CVSS score: 5.5/10. Published 2026-04-10.
- How severe is CVE-2026-40159?
- Medium severity. CVSS v3 base score is 5.5 out of 10.