Arch Linux Security Advisory ASA-202105-2

Severity: High
Date : 2021-05-19
CVE-ID : CVE-2021-21241
Package : python-flask-security-too
Type : cross-site request forgery
Remote : Yes
Link : https://security.archlinux.org/AVG-1434

Summary

The package python-flask-security-too before version 4.0.1-1 is
vulnerable to cross-site request forgery.

Resolution

Upgrade to 4.0.1-1.

pacman -Syu “python-flask-security-too>=4.0.1-1”

The problem has been fixed upstream in version 4.0.1.

Workaround

If you aren’t using authentication tokens, you can set
SECURITY_TOKEN_MAX_AGE to “0” (seconds) which should make the token
unusable.

Description

In Flask-Security-Too from version 3.3.0 and before version 3.4.5, the
/login and /change endpoints can return the authenticated user’s
authentication token in response to a GET request. Since GET requests
aren’t protected with a CSRF token, this could lead to a malicious 3rd
party site acquiring the authentication token. Version 3.4.5 and
version 4.0.0 are patched. As a workaround, if you aren’t using
authentication tokens - you can set the SECURITY_TOKEN_MAX_AGE to “0”
(seconds) which should make the token unusable.

Impact

A remote attacker could obtain a user’s authentication token from a
cross-site request.

References

https://bugs.archlinux.org/task/70041
https://github.com/Flask-Middleware/flask-security/security/advisories/GHSA-hh7m-rx4f-4vpv
https://github.com/Flask-Middleware/flask-security/issues/421
https://github.com/Flask-Middleware/flask-security/pull/422
https://github.com/Flask-Middleware/flask-security/commit/c05afe837e83f20f59c0fb409ce1240341d1ec41
https://security.archlinux.org/CVE-2021-21241