Youki is a container runtime written in Rust. In versions 0.5.6 and below, the initial validation of the source /dev/null is insufficient, allowing container escape when youki utilizes bind mounting the containers /dev/null as a file mask. This issue is fixed in version 0.5.7.
The product, when opening a file or directory, does not sufficiently account for when the file is a symbolic link that resolves to a target outside of the intended control sphere. This could allow an attacker to cause the product to operate on unauthorized files.