CVE-2021-41241

Advanced permissions is not respected for subfolders in Nextcloud server

Severity Score

4.3

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

Nextcloud server is a self hosted system designed to provide cloud style services. The groupfolders application for Nextcloud allows sharing a folder with a group of people. In addition, it allows setting "advanced permissions" on subfolders, for example, a user could be granted access to the groupfolder but not specific subfolders. Due to a lacking permission check in affected versions, a user could still access these subfolders by copying the groupfolder to another location. It is recommended that the Nextcloud Server is upgraded to 20.0.14, 21.0.6 or 22.2.1. Users unable to upgrade should disable the "groupfolders" application in the admin settings.

El servidor de Nextcloud es un sistema autoalojado diseñado para proporcionar servicios de estilo en la nube. La aplicación groupfolders para Nextcloud permite compartir una carpeta con un grupo de personas. Además, permite establecer "permisos avanzados" en las subcarpetas, por ejemplo, un usuario podría tener acceso a la carpeta de grupo pero no a subcarpetas específicas. Debido a la falta de comprobación de permisos en las versiones afectadas, un usuario podría seguir accediendo a estas subcarpetas copiando la carpeta de grupo a otra ubicación. Se recomienda actualizar el servidor Nextcloud a la versión 20.0.14, 21.0.6 o 22.2.1. Los usuarios que no puedan actualizarse deberán desactivar la aplicación "groupfolders" en la configuración del administrador

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Attack Vector

Network

Attack Complexity

Low

Authentication

Single

Confidentiality

Partial

Integrity

None

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-09-15 CVE Reserved
2022-03-08 CVE Published
2023-09-29 EPSS Updated
2024-08-04 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-862: Missing Authorization
CWE-863: Incorrect Authorization

CAPEC

References (4)

URL	Tag	Source
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-m4wp-r357-4q94	Issue Tracking

URL	Date	SRC

URL	Date	SRC
https://github.com/nextcloud/groupfolders/issues/1692	2022-10-25
https://github.com/nextcloud/server/pull/29362	2022-10-25

URL	Date	SRC
https://security.gentoo.org/glsa/202208-17	2022-10-25

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Nextcloud Search vendor "Nextcloud"		Nextcloud Server Search vendor "Nextcloud" for product "Nextcloud Server"				< 20.0.14 Search vendor "Nextcloud" for product "Nextcloud Server" and version " < 20.0.14"		-		Affected
Nextcloud Search vendor "Nextcloud"		Nextcloud Server Search vendor "Nextcloud" for product "Nextcloud Server"				>= 21.0.0 < 21.0.6 Search vendor "Nextcloud" for product "Nextcloud Server" and version " >= 21.0.0 < 21.0.6"		-		Affected
Nextcloud Search vendor "Nextcloud"		Nextcloud Server Search vendor "Nextcloud" for product "Nextcloud Server"				22.2.0 Search vendor "Nextcloud" for product "Nextcloud Server" and version "22.2.0"		-		Affected