urllib detected BAN-B310608 # Api call to read data for northumbria
609 with urllib.request.urlopen(northumbriaUrl_04_2021) as resp1:
610 northumbria2021Data = resp1.read()
611 with urllib.request.urlopen(northumbriaUrl_04_2020) as resp2:612 northumbria2020Data = resp2.read()
613 # Api call to read data for cleveland
614606 northumbriaUrl_04_2021 = getUrl("northumbria", "2021-03")
607 northumbriaUrl_04_2020 = getUrl("northumbria", "2020-04")
608 # Api call to read data for northumbria
609 with urllib.request.urlopen(northumbriaUrl_04_2021) as resp1:610 northumbria2021Data = resp1.read()
611 with urllib.request.urlopen(northumbriaUrl_04_2020) as resp2:
612 northumbria2020Data = resp2.read()553 # Api call to read data for northumbria
554 with urllib.request.urlopen(northumbriaUrl_04_2021) as resp1:
555 northumbria2021Data = resp1.read()
556 with urllib.request.urlopen(northumbriaUrl_04_2020) as resp2:557 northumbria2020Data = resp2.read()
558 # Api call to read data for cleveland
559551 # clevelandUrl_07_2021 = getUrl("cleveland", "2021-07")
552 # clevelandUrl_08_2021 = getUrl("cleveland", "2021-08")
553 # Api call to read data for northumbria
554 with urllib.request.urlopen(northumbriaUrl_04_2021) as resp1:555 northumbria2021Data = resp1.read()
556 with urllib.request.urlopen(northumbriaUrl_04_2020) as resp2:
557 northumbria2020Data = resp2.read()467 clevelandJuneData = resp4.read()
468 with urllib.request.urlopen(clevelandUrl_07_2021) as resp5:
469 clevelandJulyData = resp5.read()
470 with urllib.request.urlopen(clevelandUrl_08_2021) as resp6:471 clevelandAugustData = resp6.read()
472 # Read and load data in panada dataframe
473 json_format_cleveland_june = json.loads(clevelandJuneData)urllib not only opens http:// or https:// URLs, but also ftp:// and file://.
With this, it might be possible to open local files on the executing machine which might be a security risk if the URL to open can be manipulated by an external user.
The urllib.request module defines functions and classes which help in opening URLs. urllib.request.open can open ftp:// and file:// URLs. This is usually not intended and makes the application vulnerable to Server Side Request Forgery attack.
Performing requests from user-provided data could allow attackers to make requests on the internal network or change, retrieve or delete sensitive information. You are yourself responsible for validating the URL before opening it with urllib.
It is recommended to validate the user-provided data, such as the URL and headers used to construct the request.
Since this is an audit issue, some occurrences may be harmless here. The goal is to bring the issue in attention. Please make sure that the url is trusted. If the occurrences doesn't seem to be valid, please feel free to ignore them.
Bad practice
req = urllib.Request.request(url)
resp = urllib.request.urlopen(req)
Recommended
# Validate URL before opening it
if url.lower().startswith('http'):
req = urllib.Request.request(url)
else:
raise ValueError from None
with urllib.request.urlopen(req) as resp:
[...]
## References:
- OWASP Top 10 2021 Category A10 - [Server Side Request Forgery](https://owasp.org/Top10/A10_2021-Server-Side_Request_Forgery_%28SSRF%29/)
- [CWE-918](https://cwe.mitre.org/data/definitions/918.html) - Server-Side Request Forgery (SSRF)