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 install a malicious snap which contained non-regular files at these paths could then cause snapd to block indefinitely trying to read from such files and cause a denial of service.

The remote Ubuntu 20.04 LTS / 22.04 LTS / 24.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-6940-1 advisory.

    Neil McPhail discovered that snapd did not properly restrict writes to the $HOME/bin path in the AppArmor     profile for snaps using the home plug. An attacker who could convince a user to install a malicious snap     could use this vulnerability to escape the snap sandbox. (CVE-2024-1724)

    Zeyad Gouda discovered that snapd failed to properly check the file type when extracting a snap. An     attacker who could convince a user to install a malicious snap containing non-regular files could then     cause snapd to block indefinitely while trying to read from such files and cause a denial of service.
    (CVE-2024-29068)

    Zeyad Gouda discovered that snapd failed to properly check the destination of symbolic links when     extracting a snap. An attacker who could convince a user to install a malicious snap containing crafted     symbolic links could then cause snapd to write out the contents of the symbolic link destination into a     world-readable directory. This in-turn could allow a local unprivileged user to gain access to privileged     information. (CVE-2024-29069)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Detections

Analytics

CVE-2024-29068

medium

Tenable Plugins

high