CVE-2021-23385
When using the get_post_logout_redirect and get_post_login_redirect functions, 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.
Does this matter?
Lower severity and a low EPSS score (1.15%). Track it; it rarely justifies an emergency change on its own.
Description
This affects all versions of package Flask-Security. When using the get_post_logout_redirect and get_post_login_redirect functions, 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. 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. **Note:** Flask-Security is not maintained anymore.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 1.15% probability · 65th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-601
- Affected
- flask-security project/flask-security
- Source
- report@snyk.io
References
- https://github.com/mattupstate/flask-securityProduct, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2023/08/msg00034.html
- https://security.snyk.io/vuln/SNYK-PYTHON-FLASKSECURITY-1293234Exploit, Third Party Advisory
- https://snyk.io/blog/url-confusion-vulnerabilities/Technical Description, Third Party Advisory
- https://github.com/mattupstate/flask-securityProduct, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2023/08/msg00034.html
- https://security.snyk.io/vuln/SNYK-PYTHON-FLASKSECURITY-1293234Exploit, Third Party Advisory
- https://snyk.io/blog/url-confusion-vulnerabilities/Technical Description, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.