CVE-2021-43816
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.
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
CVSS v2 Score
AV:N/AC:M/Au:S/C:P/I:P/A:P
EPSS Score (Exploitation Probability)
This vulnerability has a 0.15% probability of being exploited in the next 30 days, ranking higher than 35% of all scored CVEs.
CWE Classification
Related Vulnerabilities
Same Weakness Type(CWE-281)
Insecure Permissions vulnerability in Open Robotics Robotic Operating System 2 ROS2 navigation2 v.humble allows an attacker to execute arbitrary code via a crafted script to the nav2_costmap_2d.
Insecure Permissions vulnerability in Open Robotics Robotic Operating System 2 ROS2 navigation2 v.humble allows an attacker to execute arbitrary code via a crafted script to the executor_thread_.
Insecure Permissions vulnerability in Open Robotics Robotic Operating System 2 ROS2 navigation2 v.humble allows an attacker to execute arbitrary code via a crafted script to the nav2_dwb_controller.
Insecure Permissions vulnerability in Open Robotics Robotic Operating System 2 ROS2 navigation2 v.humble allows an attacker to execute arbitrary code via a crafted script to the nav2__amcl.
Insecure Permissions vulnerability in Open Robotics Robotic Operating System 2 ROS2 navigation2 v.humble allows an attacker to execute arbitrary code via the dyn_param_handler_ component.
Similar SeverityHIGH
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