PT-2020-3712 · Google+1 · Google Cloud+1

Chris Moberly + 1 · Published 2020-06-19 · Updated 2024-05-21 · CVE-2020-8933

Positive Technologies (AI Summary)

CVSS v4.0

9.3

Critical

Base vector

AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Name of the Vulnerable Software and Affected Versions: Google Cloud OS guest-oslogin versions 20190304 through 20200507

Description: The issue is related to incorrect default permission settings in the guest-oslogin feature of Google Cloud OS. This allows an attacker to escalate privileges to root. By being a member of 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 gain administrative privileges.

Recommendations: For versions 20190304 through 20200507, update to an image created after 2020-May-07. As a temporary workaround for versions that cannot be updated, edit /etc/group/security.conf and remove the lxd user from the OS Login entry.

Exploit

Fix

Incorrect Default Permissions

Weakness Enumeration

CWE-276

Related Identifiers

BDU:2020-04069

CVE-2020-8933

OPENSUSE-SU-2020:0996-1

OPENSUSE-SU-2020:1014-1

OPENSUSE-SU-2020_0996-1

OPENSUSE-SU-2020_1014-1

SUSE-SU-2020:1934-1

SUSE-SU-2020:2200-1

Affected Products

Google Cloud

Suse

References · 26

• 🔥 https://gitlab.com/gitlab-com/gl-security/gl-redteam/red-team-tech-notes/-/tree/master/oslogin-privesc-june-2020 · Exploit
• https://github.com/GoogleCloudPlatform/guest-oslogin/pull/29 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2020-8933 · Security Note
• https://bdu.fstec.ru/vul/2020-04069 · Security Note
• http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00037.html · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2020-8933 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2020-8933 · Security Note
• https://cloud.google.com/support/bulletins/#gcp-2020-008 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2020:0996-1 · Vendor Advisory
• http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00047.html · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2020:1014-1 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2020:2200-1 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2020:1934-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2020-8933 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2020-8933 · Vendor Advisory