CVE-2021-41103 MEDIUM

CVE-2021-41103: Insufficiently restricted permissions on plugin directories

Vendor Containerd
Product containerd
Weakness CWE-22 · Path traversal
Published October 4, 2021
Last update August 4, 2024

CVSS base score

5.9/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

What the vulnerability does

01Description

containerd is an open source container runtime with an emphasis on simplicity, robustness and portability. A bug was found in containerd where container root directories and some plugins had insufficiently restricted permissions, allowing otherwise unprivileged Linux users to traverse directory contents and execute programs. When containers included executable programs with extended permission bits (such as setuid), unprivileged Linux users could discover and execute those programs. When the UID of an unprivileged Linux user on the host collided with the file owner or group inside a container, the unprivileged Linux user on the host could discover, read, and modify those files. This vulnerability has been fixed in containerd 1.4.11 and containerd 1.5.7. Users should update to these version when they are released and may restart containers or update directory permissions to mitigate the vulnerability. Users unable to update should limit access to the host to trusted users. Update directory permission on container bundles directories.

Key dates

02Disclosure timeline

October 4, 2021 CVE published
August 4, 2024 Record updated