USN-6940-1: snapd vulnerabilities

1 August 2024

Several security issues were fixed in snapd.

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Releases

Packages

  • snapd - Daemon and tooling that enable snap packages

Details

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)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 24.04
Ubuntu 22.04
Ubuntu 20.04

In general, a standard system update will make all the necessary changes.