Use of unsanitized data to open API

Documentos > Code Analysis > Static Analysis Rules > Use of unsanitized data to open API

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Metadata

ID: python-flask/urlopen-unsanitized-data

Language: Python

Severity: Error

Category: Security

CWE: 918

Description

Use of unsanitized from incoming request, leading to potential data leak and lack of control of the service. The code should check any incoming data and make sure it’s safe to use it.

Learn More

CWE-918: Server-Side Request Forgery (SSRF)

Non-Compliant Code Examples

import flask
from urllib.request import urlopen

app = flask.Flask(__name__)



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


@app.route("/route/to/resource")
def resource2():
    resource_id = flask.request.args.get("resource_id")
    file1 = urlopen(resource_id)
    file2 = urlopen(f"/path/to/{resource_id}")
    file3 = urlopen("/path/to/{0}".format(resource_id))

Compliant Code Examples

import flask
from urllib.request import urlopen

app = flask.Flask(__name__)

@app.route("/route/to/resource/<resource_id>")
def resource2(resource_id):
    sanitized_resource_id = sanitize(resource_id)
    file1 = urlopen(sanitized_resource_id)