Vulnerability in Google Guest-Oslogin

CVE-2020-8933

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (26.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 26.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2020-8933: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-8933?
CVE-2020-8933 is a high-severity vulnerability in Google Guest-Oslogin, classified under Incorrect Default Permissions. CVSS score: 7.8/10. Published 2020-06-22.
How severe is CVE-2020-8933?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2020-8933 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.