CVE-2021-43816
Unprivileged pod using `hostPath` can side-step active LSM when it is SELinux in github.com/containerd/containerd
描述
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.
如何修補 CVE-2021-43816
要修補 CVE-2021-43816,請將受影響套件升級到下列已修補版本。
- —升級至 1.5.9 或更新版本
CVE-2021-43816 正在被利用嗎?
低 — EPSS 為 1.7%,目前沒有觀察到大規模利用活動。
受影響套件(1)
- >= 1.5.0, < 1.5.9
CVSS 分數
| 來源 | 版本 | 嚴重程度 | 向量 |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.0 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H |