The PAM module for fscrypt doesn't adequately validate fscrypt metadata files, allowing users to create malicious metadata files that prevent other users from logging in. A local user can cause a denial of service by creating a fscrypt metadata file that prevents other users from logging into the system. We recommend upgrading to version 0.3.3 or above
fscrypt through v0.3.2 creates a world-writable directory by default when setting up a filesystem, allowing unprivileged users to exhaust filesystem space. We recommend upgrading to fscrypt 0.3.3 or above and adjusting the permissions on existing fscrypt metadata directories where applicable.
The pamfscrypt module in fscrypt before 0.2.4 may incorrectly restore primary and supplementary group IDs to the values associated with the root user, which allows attackers to gain privileges via a successful login through certain applications that use Linux-PAM (aka pam).