Arch Linux Security Advisory ASA-202105-17

Severity: High
Date    : 2021-05-25
CVE-ID  : CVE-2021-30465
Package : runc
Type    : sandbox escape
Remote  : No
Link    :


The package runc before version 1.0.0rc95-1 is vulnerable to sandbox


Upgrade to 1.0.0rc95-1.

# pacman -Syu "runc>=1.0.0rc95-1"

The problem has been fixed upstream in version 1.0.0rc95.


Container hardening mechanisms such as LSMs (AppArmor/SELinux) and user
namespaces can restrict the amount of damage an attacker could do but
they do not block this attack outright.


runc 1.0.0-rc94 and earlier are vulnerable to a symlink exchange attack
where an attacker with the ability to start containers using a custom
volume configuration can request a seemingly-innocuous container
configuration that results in the host filesystem being bind-mounted
into the container (allowing for a container escape).


An attacker can escape from a container and access arbitrary files on
the host system using a crafted container configuration.