What is CVE-2021-23393?

CVE-2021-23393 is a medium-severity vulnerability in Flask Unchained Project, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 5.4/10. Published 2021-06-11.

How severe is CVE-2021-23393?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Open Redirect in Flask Unchained Project

CVE-2021-23393

This affects the package Flask-Unchained before 0.9.0. When using the the _validate_redirect_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. 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.

Vulnerability class: Open Redirect

EPSS: 0.007 (50.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N.

Affected products

Flask_unchained_project Flask_unchained
N/a Flask-unchained — versions unspecified

Weakness classification (CWE)

CWE-601 — URL Redirection to Untrusted Site (Open Redirect)

References

report@snyk.io (Patch, Third Party Advisory, x_refsource_MISC)
report@snyk.io (Patch, Third Party Advisory, x_refsource_MISC)

Frequently asked questions

What is CVE-2021-23393?: CVE-2021-23393 is a medium-severity vulnerability in Flask Unchained Project, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 5.4/10. Published 2021-06-11.
How severe is CVE-2021-23393?: Medium severity. CVSS v3 base score is 5.4 out of 10.