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  5. CVE-2021-23401

CVE-2021-23401: Open Redirect in Flask-User

August 9, 2021 (updated September 20, 2024)

This affects all versions of package Flask-User. When using the make_safe_url function, it is possible to bypass URL validation and redirect a user to an arbitrary URL by providing multiple backslashes such as /////evil.com/path or \\\evil.com/path. This vulnerability is only exploitable if an alternative WSGI server other than Werkzeug is used, or the default behaviour of Werkzeug is modified using autocorrect_location_header=False.

References

  • github.com/advisories/GHSA-4298-89hc-6rfv
  • github.com/lingthio/Flask-User
  • github.com/lingthio/Flask-User/blob/master/flask_user/user_manager__utils.py
  • github.com/pypa/advisory-database/tree/main/vulns/flask-user/PYSEC-2021-337.yaml
  • nvd.nist.gov/vuln/detail/CVE-2021-23401
  • snyk.io/vuln/SNYK-PYTHON-FLASKUSER-1293188

Code Behaviors & Features

Detect and mitigate CVE-2021-23401 with GitLab Dependency Scanning

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Affected versions

All versions up to 1.0.2.2

Solution

Unfortunately, there is no solution available yet.

Impact 6.1 MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Learn more about CVSS

Weakness

  • CWE-601: URL Redirection to Untrusted Site ('Open Redirect')

Source file

pypi/Flask-User/CVE-2021-23401.yml

Spotted a mistake? Edit the file on GitLab.

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