Description
A vulnerability in Google Cloud Platform's guest-oslogin versions between 20190304 and 20200507 allows a user that is only granted the role "roles/compute.osLogin" to escalate privileges to root. Using the membership to the "lxd" group, an attacker can attach host devices and filesystems. Within an lxc container, it is possible to attach the host OS filesystem and modify /etc/sudoers to then gain administrative privileges. All images created after 2020-May-07 (20200507) are fixed, and if you cannot update, we recommend you edit /etc/group/security.conf and remove the "lxd" user from the OS Login entry.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Google LLC guest-oslogin
Default version status: unaffected
20190304 to < 20200507affected20200507unaffected
References
- https://github.com/GoogleCloudPlatform/guest-oslogin/pull/29 ↗
- https://gitlab.com/gitlab-com/gl-security/gl-redteam/red-team-tech-notes/-/tree/master/oslogin-privesc-june-2020 ↗
- https://cloud.google.com/support/bulletins/#gcp-2020-008 ↗
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00037.html ↗
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00047.html ↗