A snap with prior permissions to create a mount entry on the host, such as firefox, normally uses the permission from one of the per-snap hook programs. A unprivileged users cannot normally trigger that behaviour by using snap run –shell firefox followed by snapctl mount, since snapd validates the requesting user identity (root or non-root). The issue allows unprivileged users to bypass that check by crafting a malicious command line …
In snapd versions prior to 2.62, when using AppArmor for enforcement of sandbox permissions, snapd failed to restrict writes to the $HOME/bin path. In Ubuntu, when this path exists, it is automatically added to the users PATH. An attacker who could convince a user to install a malicious snap which used the 'home' plug could use this vulnerability to install arbitrary scripts into the users PATH which may then be …
In snapd versions prior to 2.62, snapd failed to properly check the file type when extracting a snap. The snap format is a squashfs file-system image and so can contain files that are non-regular files (such as pipes or sockets etc). Various file entries within the snap squashfs image (such as icons etc) are directly read by snapd when it is extracted. An attacker who could convince a user to …
In snapd versions prior to 2.62, snapd failed to properly check the destination of symbolic links when extracting a snap. The snap format is a squashfs file-system image and so can contain symbolic links and other file types. Various file entries within the snap squashfs image (such as icons and desktop files etc) are directly read by snapd when it is extracted. An attacker who could convince a user to …
Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-p9v8-q5m4-pf46. This link is maintained to preserve external references. Original Description The snapctl component within snapd allows a confined snap to interact with the snapd daemon to take certain privileged actions on behalf of the snap. It was found that snapctl did not properly parse command-line arguments, allowing an unprivileged user to trigger an authorised action on …
Race condition in snap-confine's must_mkdir_and_open_with_perms()