CVE-2021-23385

Public Exploit
Open Redirect

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.

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.18%
Third-Party Advisory github.com Third-Party Advisory snyk.io Third-Party Advisory snyk.io
Affected: n/a Flask-Security
Published at:
Updated at:

References

Link Tags
https://security.snyk.io/vuln/SNYK-PYTHON-FLASKSECURITY-1293234 third party advisory exploit
https://github.com/mattupstate/flask-security third party advisory product
https://snyk.io/blog/url-confusion-vulnerabilities/ third party advisory technical description
https://lists.debian.org/debian-lts-announce/2023/08/msg00034.html mailing list

Frequently Asked Questions

What is the severity of CVE-2021-23385?
CVE-2021-23385 has been scored as a medium severity vulnerability.
How to fix CVE-2021-23385?
To fix CVE-2021-23385, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-23385 being actively exploited in the wild?
It is possible that CVE-2021-23385 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-23385?
CVE-2021-23385 affects n/a Flask-Security.
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