CVE-2020-8933

Priviged Escalation in Google Cloud Platform's Guest-OSLogin

Severity Score

9.3

*CVSS v4

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track*

*SSVC

Descriptions

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.

Una vulnerabilidad en las versiones entre 20190304 y 20200507 de guest-oslogin de Google Cloud Platform, permite a un usuario al que solo se le otorgó el rol "roles/compute.osLogin" para escalar privilegios a root. Usando la membresía en el grupo "lxd", un atacante puede conectar dispositivos host y sistemas de archivos. Dentro de un contenedor lxc, es posible adjuntar el sistema de archivos del sistema operativo host y modificar /etc/sudoers para luego obtener privilegios administrativos. Todas las imágenes creadas después del 07 de mayo 2020 (20200507) están corregidas, y si no la pueden actualizar, le recomendamos editar /etc/group/security.conf y eliminar el usuario "lxd" desde la entrada de Inicio de Sesión del Sistema Operativo

*Credits: Chris Moberly

CVSS Scores

Attack Vector

Local

Attack Complexity

Low

Attack Requirements

None

Privileges Required

Low

User Interaction

None

System

Vulnerable | Subsequent

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Local

Attack Complexity

Medium

Authentication

None

Confidentiality

Complete

Integrity

Complete

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:Track*

Exploitation

None

Automatable

Tech. Impact

Total

* Organization's Worst-case Scenario

Timeline

2020-02-12 CVE Reserved
2020-06-22 CVE Published
2023-03-08 EPSS Updated
2024-08-04 CVE Updated
2024-08-04 First Exploit
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-276: Incorrect Default Permissions

CAPEC

References (5)

URL	Tag	Source

URL	Date	SRC
https://gitlab.com/gitlab-com/gl-security/gl-redteam/red-team-tech-notes/-/tree/master/oslogin-privesc-june-2020	2024-08-04

URL	Date	SRC
https://github.com/GoogleCloudPlatform/guest-oslogin/pull/29	2024-05-21

URL	Date	SRC
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00037.html	2024-05-21
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00047.html	2024-05-21
https://cloud.google.com/support/bulletins/#gcp-2020-008	2024-05-21

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Google Search vendor "Google"		Guest-oslogin Search vendor "Google" for product "Guest-oslogin"				>= 20190304.00 <= 20200507.00 Search vendor "Google" for product "Guest-oslogin" and version " >= 20190304.00 <= 20200507.00"		-		Affected
Opensuse Search vendor "Opensuse"		Leap Search vendor "Opensuse" for product "Leap"				15.1 Search vendor "Opensuse" for product "Leap" and version "15.1"		-		Affected
Opensuse Search vendor "Opensuse"		Leap Search vendor "Opensuse" for product "Leap"				15.2 Search vendor "Opensuse" for product "Leap" and version "15.2"		-		Affected