# CVE-2026-40159: MervinPraison PraisonAI sensitive information exposure in MCP integration

Source: https://junglewise.ai/threats/cve-2026-40159-mervinpraison-praisonai-sensitive-information-exposure-in-mcp  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-10. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2026-40159 · Severity: medium · CVSS 5.5 · Published 2026-04-10

PraisonAI, an AI agent framework, contains a security flaw in how it handles background tasks. When the software runs third-party tools or servers, it inadvertently shares all of the main application's secret keys and credentials with those tools. This could allow a malicious third-party package to steal sensitive information like OpenAI API keys, database passwords, or cloud access tokens.

Technologies: [Praisonai](https://junglewise.ai/threats/technologies/praisonai), [praisonai (PyPI)](https://junglewise.ai/threats/technologies/pypi-praisonai). Vendors: [Praison](https://junglewise.ai/threats/vendors/praison), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-40159 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-40159 being exploited in the wild.

**How severe is CVE-2026-40159?** Medium severity, with a CVSS score of 5.5, published 10 April 2026.

**Which products and versions are affected?** praisonai (PyPI) ECOSYSTEM:introduced=0,fixed=4.5.128.

**Is there a fix for CVE-2026-40159?** Yes. praisonai (PyPI): upgrade to 4.5.128 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-40159 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-40159?** Check whether you run Praisonai or praisonai (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- praisonai (PyPI): upgrade to 4.5.128 or later

  ```sh
  pip install "praisonai>=4.5.128"
  ```


## Technical details

PraisonAI's Model Context Protocol (MCP) integration uses Python's subprocess module to spawn background servers. By default, the implementation in `mcp.py` copies the entire parent process environment (`os.environ.copy()`) and forwards it to the child process if no specific environment is provided. An attacker can exploit this by providing a malicious command string to the MCP constructor. When executed, the subprocess inherits all sensitive environment variables, such as `OPENAI_API_KEY` or database connection strings, which can then be exfiltrated to a remote server. This vulnerability is tracked as CVE-2026-40159 and is fixed in version 4.5.128.

## Affected products

- MervinPraison PraisonAI < 4.5.128

## Identifiers

- CVE-2026-40159
- GHSA-pj2r-f9mw-vrcq
- PYSEC-2026-2918

## Timeline

- 2026-04-09: disclosed: Vulnerability published by MervinPraison
- 2026-04-10: advisory: GitHub Advisory GHSA-pj2r-f9mw-vrcq published
- 2026-04-10: patched: Fixed in version 4.5.128

## References

- [https://api.github.com/users/l3tchupkt](https://api.github.com/users/l3tchupkt)
- [https://github.com/l3tchupkt](https://github.com/l3tchupkt)
- [https://api.github.com/users/l3tchupkt/gists%7B/gist_id%7D](https://api.github.com/users/l3tchupkt/gists%7B/gist_id%7D)
- [https://api.github.com/users/l3tchupkt/repos](https://api.github.com/users/l3tchupkt/repos)
- [https://avatars.githubusercontent.com/u/191794587?v=4](https://avatars.githubusercontent.com/u/191794587?v=4)
- [https://api.github.com/users/l3tchupkt/events%7B/privacy%7D](https://api.github.com/users/l3tchupkt/events%7B/privacy%7D)

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