USN-5292-3: snapd vulnerabilities
18 February 2022
Several security issues were fixed in snapd.
Releases
Packages
- snapd - Daemon and tooling that enable snap packages
Details
USN-5292-1 fixed several vulnerabilities in snapd. This update provides the
corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.
Original advisory details:
James Troup discovered that snap did not properly manage the permissions for
the snap directories. A local attacker could possibly use this issue to expose
sensitive information. (CVE-2021-3155)
Ian Johnson discovered that snapd did not properly validate content interfaces
and layout paths. A local attacker could possibly use this issue to inject
arbitrary AppArmor policy rules, resulting in a bypass of intended access
restrictions. (CVE-2021-4120)
The Qualys Research Team discovered that snapd did not properly validate the
location of the snap-confine binary. A local attacker could possibly use this
issue to execute other arbitrary binaries and escalate privileges.
(CVE-2021-44730)
The Qualys Research Team discovered that a race condition existed in the snapd
snap-confine binary when preparing a private mount namespace for a snap. A
local attacker could possibly use this issue to escalate privileges and
execute arbitrary code. (CVE-2021-44731)
Update instructions
The problem can be corrected by updating your system to the following package versions:
Ubuntu 16.04
-
snap-confine
-
2.54.3+16.04~esm2
Available with Ubuntu Pro
-
snapd
-
2.54.3+16.04~esm2
Available with Ubuntu Pro
Ubuntu 14.04
-
snap-confine
-
2.54.3+14.04~esm1
Available with Ubuntu Pro
-
snapd
-
2.54.3+14.04~esm1
Available with Ubuntu Pro
In general, a standard system update will make all the necessary changes.