Google Cloud Platform · Guest-Oslogin · CVE-2020-8907
Name of the Vulnerable Software and Affected Versions:
Google Cloud Platform's guest-oslogin versions between 20190304 and 20200507
Description:
A vulnerability in Google Cloud Platform's guest-oslogin allows a user with the role "roles/compute.osLogin" to escalate privileges to root. Using their membership to the "docker" group, an attacker with this role is able to run docker and mount the host OS. Within docker, it is possible to modify the host OS filesystem and modify /etc/groups to gain administrative privileges.
Recommendations:
For versions between 20190304 and 20200507, if an update to a newer version is not possible, edit /etc/group/security.conf and remove the "docker" user from the OS Login entry to mitigate the issue.
At the moment, there is no information about a newer version that contains a fix for this vulnerability, but it is known that all images created after 2020-May-07 are fixed.