CVE-2021-23385 · cross-distro fix matrix

CVE-2021-23385: 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

Affects 3 Linux releases across 3 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-23385 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

flask-security→ fixed in4.0.0-1+deb11u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y flask-security
```

Debian bookworm

Source: Debian Security Tracker

flask-security→ fixed in5.0.2-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y flask-security
```

Debian trixie

Source: Debian Security Tracker

flask-security→ fixed in5.0.2-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y flask-security
```

Are YOU affected by CVE-2021-23385?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan View on NVD

Continuous monitoring beats manual checking

CVE-2021-23385dropped silently in your distro's update channel. Every new CVE is the same story. StackPatch runs the matcher hourly against all 5 sources and emails the exact remediation when something new applies to one of your servers. $99 lifetime, 50 founder seats, 30-day refund.

See StackPatch ($99 lifetime)