Privilege escalation via supplementary groups in github.com/containerd/containerd

Open Source Vulnerabilities GO-2023-1574

Supplementary groups are not set up properly inside a container. If an attacker has direct access to a container and manipulates their supplementary group access, they may be able to use supplementary group access to bypass primary group restrictions in some cases and potentially escalate privileges in the container. Uses of the containerd client library may also have improperly setup supplementary groups.

Open Source Vulnerabilities GHSA-hmfx-3pcx-653p

### Impact A bug was found in containerd where supplementary groups are not set up properly inside a container. If an attacker has direct access to a container and manipulates their supplementary group access, they may be able to use supplementary group access to bypass primary group restrictions in some cases, potentially gaining access to sensitive information or gaining the ability to execute code in that container. Downstream applications that use the containerd client library may be affected as well. ### Patches This bug has been fixed in containerd v1.6.18 and v.1.5.18. Users should update to these versions and recreate containers to resolve this issue. Users who rely on a downstream application that uses containerd's client library should check that application for a separate advisory and instructions. ### Workarounds Ensure that the `"USER $USERNAME"` Dockerfile instruction is not used. Instead, set the container entrypoint to a value similar to `ENTRYPOINT ["su", "-", "user"]` to allow `su` to properly set up supplementary groups. ### References - https://www.benthamsgaze.org/2022/08/22/vulnerability-in-linux-containers-investigation-and-mitigation/ - Docker/Moby: CVE-2022-36109, fixed in Docker 20.10.18 - CRI-O: CVE-2022-2995, fixed in CRI-O 1.25.0 - Podman: CVE-2022-2989, fixed in Podman 3.0.1 and 4.2.0 - Buildah: CVE-2022-2990, fixed in Buildah 1.27.1 Note that CVE IDs apply to a particular implementation, even if an issue is common. ### For more information If you have any questions or comments about this advisory: * Open an issue in [containerd](https://github.com/containerd/containerd/issues/new/choose) * Email us at [[email protected]](mailto:[email protected]) To report a security issue in containerd: * [Report a new vulnerability](https://github.com/containerd/containerd/security/advisories/new) * Email us at [[email protected]](mailto:[email protected])

Open Source Vulnerabilities CVE-2023-25173

containerd is an open source container runtime. A bug was found in containerd prior to versions 1.6.18 and 1.5.18 where supplementary groups are not set up properly inside a container. If an attacker has direct access to a container and manipulates their supplementary group access, they may be able to use supplementary group access to bypass primary group restrictions in some cases, potentially gaining access to sensitive information or gaining the ability to execute code in that container. Downstream applications that use the containerd client library may be affected as well. This bug has been fixed in containerd v1.6.18 and v.1.5.18. Users should update to these versions and recreate containers to resolve this issue. Users who rely on a downstream application that uses containerd's client library should check that application for a separate advisory and instructions. As a workaround, ensure that the `"USER $USERNAME"` Dockerfile instruction is not used. Instead, set the container entrypoint to a value similar to `ENTRYPOINT ["su", "-", "user"]` to allow `su` to properly set up supplementary groups.