CVE-2026-40159

PraisonAI Exposes Sensitive Environment Variable via Untrusted MCP Subprocess Execution

At a glance

Severity
MEDIUM 5.5
EPSS
EPSS 0.18 % · percentile 8 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
GitHub_M
NVD status
Analyzed

Description

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.

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 5.5CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:NGitHub_M
CVSS 3.1MEDIUM 5.5CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:NNVD · security-advisories@github.com (Secondary)

Weaknesses (CWE)

Advisories

European references

Affected configurations (NVD CPE)

Affected products

ProductVersions
MervinPraison · PraisonAIaffected < 4.5.128

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD