Debian Security Advisory

DLA-3369-1 runc -- LTS security update

Date Reported:
27 Mar 2023
Affected Packages:
Security database references:
In the Debian bugtracking system: Bug 942026, Bug 988768.
In Mitre's CVE dictionary: CVE-2019-16884, CVE-2019-19921, CVE-2021-30465, CVE-2022-29162, CVE-2023-27561.
More information:

Multiple vulnerabilities were discovered in runc, the Open Container Project runtime, which is often used with virtualization environments such as Docker. Malicious Docker images or OCI bundles could breach isolation.

  • CVE-2019-16884

    runc, as used in Docker and other products, allows AppArmor and SELinux restriction bypass because libcontainer/rootfs_linux.go incorrectly checks mount targets, and thus a malicious Docker image can mount over a /proc directory.

  • CVE-2019-19921

    runc has Incorrect Access Control leading to Escalation of Privileges, related to libcontainer/rootfs_linux.go. To exploit this, an attacker must be able to spawn two containers with custom volume-mount configurations, and be able to run custom images. (This vulnerability does not affect Docker due to an implementation detail that happens to block the attack.)

  • CVE-2021-30465

    runc allows a Container Filesystem Breakout via Directory Traversal. To exploit the vulnerability, an attacker must be able to create multiple containers with a fairly specific mount configuration. The problem occurs via a symlink-exchange attack that relies on a race condition.

  • CVE-2022-29162

    `runc exec --cap` created processes with non-empty inheritable Linux process capabilities, creating an atypical Linux environment and enabling programs with inheritable file capabilities to elevate those capabilities to the permitted set during execve(2). This bug did not affect the container security sandbox as the inheritable set never contained more capabilities than were included in the container's bounding set.

  • CVE-2023-27561

    CVE-2019-19921 was re-introduced by the fix for CVE-2021-30465.

For Debian 10 buster, this problem has been fixed in version 1.0.0~rc6+dfsg1-3+deb10u2.

We recommend that you upgrade your runc packages.

For the detailed security status of runc please refer to its security tracker page at:

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: