by Kastro
Paper/Archive/CVE-2020-8933

CVE-2020-8933

Google LLC guest-oslogin — Priviged Escalation in Google Cloud Platform's Guest-OSLogin

EPSS 0.4%CVSS 9.3
critical.is priorityof 100
34
CVSS 9.3 (CNA)9.3 / 10 × 3027.9Not in CISA KEV+300.0EPSS percentile 29.0.290 × 205.8No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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

ProductAffectedFixed inSource
guest-oslogin20190304 – < 2020050720200507CNA
guest-oslogin20190304.00 – < 2020050720200507CISA-ADP

Scores by source

Google (CNA)9.3CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

refgithub.com/GoogleCloudPlatform/guest-oslogin/pull/29refgitlab.com/gitlab-com/gl-security/gl-redteam/red-team-tech-notes/-/tree/master/oslogin-privesc-june-2020refcloud.google.com/support/bulletins/#gcp-2020-008advisorylists.opensuse.org/opensuse-security-announce/2020-07/msg00037.htmladvisorylists.opensuse.org/opensuse-security-announce/2020-07/msg00047.html