CVEvulnerability

CVE-2021-23401

6.1 MEDIUM Published 2021-07-05 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2021-07-05
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
5.4 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
CVSS 3.1 ([email protected])
6.1 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CVSS 2.0 ([email protected])
5.8 MEDIUM — AV:N/AC:M/Au:N/C:P/I:P/A:N
Weaknesses
CWE-601

Description

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 back slashes 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.

Affected configurations

• flask-user project flask-user

Related

Weakness · CWE (1)

  • CWE-601 URL Redirection to Untrusted Site weakness

References