CVE-2026-40156
PraisonAI Affected by Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.8
PraisonAI Affected by Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading
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.
- Record
CVE-2026-40156- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-94, CWE-426, CWE-829
- Updated
- 2026-11-02
EUVDEUVD-2026-21508
7.8
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.
- Record
EUVD-2026-21508- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-2g3w-cpc4-chr4
7.8
PraisonAI Vulnerable to Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading
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
- Create a malicious
tools.pyin 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"
-
Create any valid
agents.yaml. -
Run:
praisonai agents.yaml
- Observe:
[PWNED]is printedpwned.txtis created- 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
-
Require explicit opt-in for loading
tools.py- Introduce a CLI flag (e.g.,
--load-tools) or config option - Disable automatic loading by default
- Introduce a CLI flag (e.g.,
-
Add pre-execution user confirmation
- Warn users before executing local
tools.py - Allow users to decline execution
- Warn users before executing local
-
Restrict trusted paths
- Only load tools from explicitly defined project directories
- Avoid defaulting to the current working directory
-
Avoid executing module-level code during discovery
- Use static analysis (e.g., AST parsing) to identify tool functions
- Require explicit registration functions instead of import side effects
-
Optional hardening
- Support sandboxed execution (subprocess / restricted environment)
- Provide hash verification or signing for trusted tool files
- Record
GHSA-2g3w-cpc4-chr4- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-94, CWE-426, CWE-829
- Updated
- 2026-11-02
NVD
7.8
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.
- Record
CVE-2026-40156- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-94, CWE-426, CWE-829
- Updated
- 2026-11-02
OSV
7.8
PraisonAI Affected by Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading
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.
- Record
CVE-2026-40156- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-426, CWE-829, CWE-94
- Updated
- 2026-11-02
OSVGHSA-2g3w-cpc4-chr4
7.8
PraisonAI Vulnerable to Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading
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
- Create a malicious
tools.pyin 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"
-
Create any valid
agents.yaml. -
Run:
praisonai agents.yaml
- Observe:
[PWNED]is printedpwned.txtis created- 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
-
Require explicit opt-in for loading
tools.py- Introduce a CLI flag (e.g.,
--load-tools) or config option - Disable automatic loading by default
- Introduce a CLI flag (e.g.,
-
Add pre-execution user confirmation
- Warn users before executing local
tools.py - Allow users to decline execution
- Warn users before executing local
-
Restrict trusted paths
- Only load tools from explicitly defined project directories
- Avoid defaulting to the current working directory
-
Avoid executing module-level code during discovery
- Use static analysis (e.g., AST parsing) to identify tool functions
- Require explicit registration functions instead of import side effects
-
Optional hardening
- Support sandboxed execution (subprocess / restricted environment)
- Provide hash verification or signing for trusted tool files
- Record
GHSA-2g3w-cpc4-chr4- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-426, CWE-829, CWE-94
- Updated
- 2026-11-02
OSVPYSEC-2026-2895
7.8
PraisonAI Vulnerable to Implicit Execution of Arbitrary Code via Automatic `tools.py` Loading
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
- Create a malicious
tools.pyin 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"
-
Create any valid
agents.yaml. -
Run:
praisonai agents.yaml
- Observe:
[PWNED]is printedpwned.txtis created- 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
-
Require explicit opt-in for loading
tools.py- Introduce a CLI flag (e.g.,
--load-tools) or config option - Disable automatic loading by default
- Introduce a CLI flag (e.g.,
-
Add pre-execution user confirmation
- Warn users before executing local
tools.py - Allow users to decline execution
- Warn users before executing local
-
Restrict trusted paths
- Only load tools from explicitly defined project directories
- Avoid defaulting to the current working directory
-
Avoid executing module-level code during discovery
- Use static analysis (e.g., AST parsing) to identify tool functions
- Require explicit registration functions instead of import side effects
-
Optional hardening
- Support sandboxed execution (subprocess / restricted environment)
- Provide hash verification or signing for trusted tool files
- Record
PYSEC-2026-2895- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
praisonaiPyPI |
before 4.5.128 | 4.5.128 |
praisonaiPyPI |
before 4.5.128, plus listed versions 0.0.10.0.100.0.110.0.120.0.13 Show 45 moreShow less0.0.140.0.150.0.160.0.170.0.180.0.190.0.20.0.200.0.210.0.220.0.230.0.240.0.250.0.260.0.270.0.280.0.290.0.30.0.300.0.310.0.320.0.330.0.340.0.350.0.360.0.370.0.380.0.390.0.40.0.400.0.410.0.420.0.430.0.440.0.450.0.460.0.470.0.480.0.490.0.50.0.500.0.520.0.530.0.540.0.55 |
4.5.128 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-40156 is a high vulnerability (CVSS 7.8) in Mervinpraison Praisonai, published April 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.22%, the 12th percentile. Fixed in praisonai 4.5.128.
References
github.com/MervinPraison/PraisonAI/security/advisories/GHSA-2g3w-cpc4-chr4
nvd.nist.gov/vuln/detail/CVE-2026-40156
github.com/MervinPraison/PraisonAI/releases/tag/v4.5.128
github.com/advisories/GHSA-2g3w-cpc4-chr4
github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40156.json
github.com/MervinPraison/PraisonAI
pypi.org/project/praisonai
Left out here: 635 versions. The JSON record has them.