CVE-2021-23393 is a URL validation bypass vulnerability in Flask-Unchained versions prior to 0.9.0. It allows an attacker to redirect users to arbitrary URLs by manipulating backslashes in the redirect URL, specifically when an alternative WSGI server or modified Werkzeug configuration is in use. This medium-severity vulnerability (CVSS 5.4) has a low attack complexity and can lead to information disclosure and integrity impacts. While there is no evidence of active exploitation or public exploit code, the vulnerability has garnered some community discussion and media coverage, indicating awareness within the security community.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 0.9.0CPE matchmatch criteria | cpe:2.3:a:flask_unchained_project:flask_unchained:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.