10 subprocess.run(['npm', 'install'], check=True)
11 elif os.path.exists('requirements.txt'):
12 print("Installing dependencies from requirements.txt...")
13 subprocess.run(['pip', 'install', '-r', 'requirements.txt'], check=True)14 else:
15 print("No package.json or requirements.txt file found. Please provide a package.json or requirements.txt file to install dependencies.")
7 """
8 if os.path.exists('package.json'):
9 print("Installing dependencies from package.json...")
10 subprocess.run(['npm', 'install'], check=True)11 elif os.path.exists('requirements.txt'):
12 print("Installing dependencies from requirements.txt...")
13 subprocess.run(['pip', 'install', '-r', 'requirements.txt'], check=True)Python possesses many mechanisms to invoke an external executable. If the desired executable path is not fully qualified relative to the filesystem root then this may present a potential security risk.
In POSIX environments, the PATH environment variable is used to specify a set of standard locations that will be searched for the first matching named executable. While convenient, this behavior may allow a malicious actor to exert control over a system. If they are able to adjust the contents of the PATH variable, or manipulate the file system, then a bogus executable may be discovered in place of the desired one. This executable will be invoked with the user privileges of the Python process that spawned it, potentially a highly privileged user.
This test will scan the parameters of all configured Python methods, looking for paths that do not start at the filesystem root, that is, do not have a leading ‘/’ character.
Bad practice
import subprocess
subprocess.run(['calculator', '-u', 'critical', msg], check=True) # Sensitive, Path not qualified from root
Recommended
import subprocess
subprocess.run(['/usr/bin/calculator', '-u', 'critical', msg], check=True) # Path qualified from root
References:
- Bandit B607
- OWASP Top 10 2021 Category A03 - Injection