==========================================================================
Ubuntu Security Notice USN-6940-1
August 01, 2024

snapd vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 24.04 LTS
- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS

Summary:

Several security issues were fixed in snapd.

Software Description:
- 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)

Update instructions:

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

Ubuntu 24.04 LTS
  snapd                           2.63+24.04ubuntu0.1

Ubuntu 22.04 LTS
  snapd                           2.63+22.04ubuntu0.1

Ubuntu 20.04 LTS
  snapd                           2.63+20.04ubuntu0.1

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

References:
  https://ubuntu.com/security/notices/USN-6940-1
  CVE-2024-1724, CVE-2024-29068, CVE-2024-29069

Package Information:
  https://launchpad.net/ubuntu/+source/snapd/2.63+24.04ubuntu0.1
  https://launchpad.net/ubuntu/+source/snapd/2.63+22.04ubuntu0.1
  https://launchpad.net/ubuntu/+source/snapd/2.63+20.04ubuntu0.1