CVE-2020-8933 Information

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.

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Reference

http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00037.html http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00047.html https://cloud.google.com/support/bulletins/gcp-2020-008 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

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

7.8