CVE-2021-43816

Improper Preservation of Permissions in containerd

State
Published
Severity
8.0 High
Published
Jan 5, 2022
Updated
Apr 22, 2025
Reserved
Nov 16, 2021

Read the record on cve.org

Description

containerd is an open source container runtime. On installations using SELinux, such as EL8 (CentOS, RHEL), Fedora, or SUSE MicroOS, with containerd since v1.5.0-beta.0 as the backing container runtime interface (CRI), an unprivileged pod scheduled to the node may bind mount, via hostPath volume, any privileged, regular file on disk for complete read/write access (sans delete). Such is achieved by placing the in-container location of the hostPath volume mount at either `/etc/hosts`, `/etc/hostname`, or `/etc/resolv.conf`. These locations are being relabeled indiscriminately to match the container process-label which effectively elevates permissions for savvy containers that would not normally be able to access privileged host files. This issue has been resolved in version 1.5.9. Users are advised to upgrade as soon as possible.

Scores

CVSSScoreVectorSource
3.18.0 HighCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:HGitHub_M

Weaknesses

  • CWE-281 Improper Preservation of Permissions

Affected Products

ProductVersions
containerdcontainerd
  • >= 1.5.0, < 1.5.9Affected

References

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.