GHSA-2G3W-CPC4-CHR4

Vulnerability from github – Published: 2026-04-10 19:26 – Updated: 2026-04-10 19:26
VLAI?
Summary
PraisonAI Vulnerable to Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading
Details

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.

Vulnerable Code Location

src/praisonai/praisonai/tool_resolver.py → ToolResolver._load_local_tools

tools_path = Path(self._tools_py_path)  # defaults to "tools.py" in CWD
...
spec = importlib.util.spec_from_file_location("tools", str(tools_path))
module = importlib.util.module_from_spec(spec)
spec.loader.exec_module(module)  # Executes arbitrary code

Reproducing the Attack

  1. Create a malicious tools.py in the target directory:
import os

# Executes immediately on import
print("[PWNED] Running arbitrary attacker code")
os.system("echo RCE confirmed > pwned.txt")

def dummy_tool():
    return "ok"

  1. Create any valid agents.yaml.

  2. Run:

praisonai agents.yaml

  1. Observe:

  2. [PWNED] is printed

  3. pwned.txt is created
  4. No warning or confirmation is shown

Real-world Impact

This issue introduces a software supply chain risk. If an attacker introduces a malicious tools.py into a repository (e.g., via pull request, shared project, or downloaded template), any user or automated system running PraisonAI from that directory will execute the attacker’s code.

Affected scenarios include:

  • CI/CD pipelines processing untrusted repositories
  • Shared development environments
  • AI workflow automation systems
  • Public project templates or examples

Successful exploitation can lead to:

  • Execution of arbitrary commands
  • Exfiltration of environment variables and credentials
  • Persistence mechanisms on developer or CI systems

Remediation Steps

  1. Require explicit opt-in for loading tools.py

  2. Introduce a CLI flag (e.g., --load-tools) or config option

  3. Disable automatic loading by default

  4. Add pre-execution user confirmation

  5. Warn users before executing local tools.py

  6. Allow users to decline execution

  7. Restrict trusted paths

  8. Only load tools from explicitly defined project directories

  9. Avoid defaulting to the current working directory

  10. Avoid executing module-level code during discovery

  11. Use static analysis (e.g., AST parsing) to identify tool functions

  12. Require explicit registration functions instead of import side effects

  13. Optional hardening

  14. Support sandboxed execution (subprocess / restricted environment)

  15. Provide hash verification or signing for trusted tool files
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "praisonai"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.5.128"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40156"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-426",
      "CWE-829",
      "CWE-94"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-10T19:26:44Z",
    "nvd_published_at": "2026-04-10T17:17:13Z",
    "severity": "HIGH"
  },
  "details": "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**.\n\nThe `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.\n\nThis 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.\n\nIf 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.\n\n---\n\n## Vulnerable Code Location\n\n`src/praisonai/praisonai/tool_resolver.py` \u2192 `ToolResolver._load_local_tools`\n\n```python\ntools_path = Path(self._tools_py_path)  # defaults to \"tools.py\" in CWD\n...\nspec = importlib.util.spec_from_file_location(\"tools\", str(tools_path))\nmodule = importlib.util.module_from_spec(spec)\nspec.loader.exec_module(module)  # Executes arbitrary code\n```\n\n---\n\n## Reproducing the Attack\n\n1. Create a malicious `tools.py` in the target directory:\n\n```python\nimport os\n\n# Executes immediately on import\nprint(\"[PWNED] Running arbitrary attacker code\")\nos.system(\"echo RCE confirmed \u003e pwned.txt\")\n\ndef dummy_tool():\n    return \"ok\"\n```\n\n2. Create any valid `agents.yaml`.\n\n3. Run:\n\n```bash\npraisonai agents.yaml\n```\n\n4. Observe:\n\n* `[PWNED]` is printed\n* `pwned.txt` is created\n* No warning or confirmation is shown\n\n---\n\n## Real-world Impact\n\nThis issue introduces a **software supply chain risk**. If an attacker introduces a malicious `tools.py` into a repository (e.g., via pull request, shared project, or downloaded template), any user or automated system running PraisonAI from that directory will execute the attacker\u2019s code.\n\nAffected scenarios include:\n\n* CI/CD pipelines processing untrusted repositories\n* Shared development environments\n* AI workflow automation systems\n* Public project templates or examples\n\nSuccessful exploitation can lead to:\n\n* Execution of arbitrary commands\n* Exfiltration of environment variables and credentials\n* Persistence mechanisms on developer or CI systems\n\n---\n\n## Remediation Steps\n\n1. **Require explicit opt-in for loading `tools.py`**\n\n   * Introduce a CLI flag (e.g., `--load-tools`) or config option\n   * Disable automatic loading by default\n\n2. **Add pre-execution user confirmation**\n\n   * Warn users before executing local `tools.py`\n   * Allow users to decline execution\n\n3. **Restrict trusted paths**\n\n   * Only load tools from explicitly defined project directories\n   * Avoid defaulting to the current working directory\n\n4. **Avoid executing module-level code during discovery**\n\n   * Use static analysis (e.g., AST parsing) to identify tool functions\n   * Require explicit registration functions instead of import side effects\n\n5. **Optional hardening**\n\n   * Support sandboxed execution (subprocess / restricted environment)\n   * Provide hash verification or signing for trusted tool files",
  "id": "GHSA-2g3w-cpc4-chr4",
  "modified": "2026-04-10T19:26:44Z",
  "published": "2026-04-10T19:26:44Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-2g3w-cpc4-chr4"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40156"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/MervinPraison/PraisonAI"
    },
    {
      "type": "WEB",
      "url": "https://github.com/MervinPraison/PraisonAI/releases/tag/v4.5.128"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "PraisonAI Vulnerable to Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading"
}


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