CVE-2021-3733

2022-03-0700:00:00

CWE-400

redhat

www.cve.org

urllib

abstractbasicauthhandler

redos

crafted payload

application availability

AI Score

7.3

Confidence

High

EPSS

0.003

Percentile

71.6%

JSON

There’s a flaw in urllib’s AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of Service (ReDOS) during an authentication request with a specially crafted payload that is sent by the server to the client. The greatest threat that this flaw poses is to application availability.

CNA Affected

[
  {
    "vendor": "n/a",
    "product": "python",
    "versions": [
      {
        "version": "Fixed in python v3.6.14, python v3.7.11, python v3.8.10, python v3.9.5.",
        "status": "affected"
      }
    ]
  }
]