Use of unsanitized data to create processes

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Metadata

ID: python-flask/os-system-unsanitized-data

Language: Python

Severity: Error

Category: Security

CWE: 78

Description

Use of unsanitized from incoming request to execute a command may lead to command injection. It is highly recommended that data is checked and sanitized before use.

Learn More

CWE-78: roper Neutralization of Special Elements used in an OS

Non-Compliant Code Examples

import flask
import os

app = flask.Flask(__name__)



@app.route("/route/to/resource/<resource_id>")
def resource2(resource_id):
    file1 = subprocess.call(resource_id)
    file2 = subprocess.capture_output(f"/path/to/{resource_id}")

@app.route("/route/to/resource/<resource_id>")
def resource2(resource_id):
    file4 = os.system("/path/to/{0}".format(resource_id))
    os.system(request.remote_addr)
    bla = os.system(request.foo)

@app.route("/route/to/resource")
def resource2():
    resource_id = flask.request.args.get("resource_id")
    subprocess.call(resource_id)
    subprocess.run(["command", resource_id])

Compliant Code Examples

import flask
import os

app = flask.Flask(__name__)

@app.route("/route/to/resource/<resource_id>")
def resource2(resource_id):
    file1 = subprocess.call(sanitize(resource_id))
    file2 = subprocess.capture_output(f"/path/to/{sanitize(resource_id)}")