CVE-2026-40156
PraisonAI Affected by Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading
Description
PraisonAI is a multi-agent teams system. Prior to 4.5.128, PraisonAI automatically loads a file named tools.py from the current working directory to discover and register custom agent tools. This loading process uses importlib.util.spec_from_file_location and immediately executes module-level code via spec.loader.exec_module() without explicit user consent, validation, or sandboxing. The tools.py file is loaded implicitly, even when it is not referenced in configuration files or explicitly requested by the user. As a result, merely placing a file named tools.py in the working directory is sufficient to trigger code execution. This behavior violates the expected security boundary between user-controlled project files (e.g., YAML configurations) and executable code, as untrusted content in the working directory is treated as trusted and executed automatically. If an attacker can place a malicious tools.py file into a directory where a user or automated system (e.g., CI/CD pipeline) runs praisonai, arbitrary code execution occurs immediately upon startup, before any agent logic begins. This vulnerability is fixed in 4.5.128.
INFO
Published Date :
April 10, 2026, 5:17 p.m.
Last Modified :
April 20, 2026, 7:56 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-40156
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update PraisonAI to version 4.5.128 or later.
- Remove untrusted tools.py files from working directories.
- Validate all files before running PraisonAI.
- Avoid running PraisonAI in untrusted directories.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-40156.
| URL | Resource |
|---|---|
| https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-2g3w-cpc4-chr4 | Vendor Advisory |
| https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-2g3w-cpc4-chr4 | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-40156 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-40156
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-40156 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-40156 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 20, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:praison:praisonai:*:*:*:*:*:*:*:* versions up to (excluding) 4.5.128 Added Reference Type CISA-ADP: https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-2g3w-cpc4-chr4 Types: Vendor Advisory Added Reference Type GitHub, Inc.: https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-2g3w-cpc4-chr4 Types: Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Apr. 13, 2026
Action Type Old Value New Value Added Reference https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-2g3w-cpc4-chr4 -
New CVE Received by [email protected]
Apr. 10, 2026
Action Type Old Value New Value Added Description PraisonAI is a multi-agent teams system. Prior to 4.5.128, PraisonAI automatically loads a file named tools.py from the current working directory to discover and register custom agent tools. This loading process uses importlib.util.spec_from_file_location and immediately executes module-level code via spec.loader.exec_module() without explicit user consent, validation, or sandboxing. The tools.py file is loaded implicitly, even when it is not referenced in configuration files or explicitly requested by the user. As a result, merely placing a file named tools.py in the working directory is sufficient to trigger code execution. This behavior violates the expected security boundary between user-controlled project files (e.g., YAML configurations) and executable code, as untrusted content in the working directory is treated as trusted and executed automatically. If an attacker can place a malicious tools.py file into a directory where a user or automated system (e.g., CI/CD pipeline) runs praisonai, arbitrary code execution occurs immediately upon startup, before any agent logic begins. This vulnerability is fixed in 4.5.128. Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Added CWE CWE-94 Added CWE CWE-426 Added CWE CWE-829 Added Reference https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-2g3w-cpc4-chr4