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. https://github.com/containerd/containerd/security/advisories/GHSA-mvff-h3cj-wj9c https://github.com/containerd/containerd/issues/6194 https://github.com/dweomer/containerd/commit/f7f08f0e34fb97392b0d382e58916d6865100299 https://github.com/containerd/containerd/commit/a731039238c62be081eb8c31525b988415745eea
Created containerd tracking bugs for this issue: Affects: epel-7 [bug 2044435] Affects: fedora-all [bug 2044436]
This issue has been addressed in the following products: Red Hat Advanced Cluster Management for Kubernetes 2.4 for RHEL 8 Via RHSA-2022:0735 https://access.redhat.com/errata/RHSA-2022:0735
This issue has been addressed in the following products: Red Hat Advanced Cluster Management for Kubernetes 2.5 for RHEL 8 Via RHSA-2022:4956 https://access.redhat.com/errata/RHSA-2022:4956
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2021-43816