// For flags

CVE-2021-41179

Two-Factor Authentication not enforced for pages marked as public

Severity Score

6.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

Nextcloud is an open-source, self-hosted productivity platform. Prior to Nextcloud Server versions 20.0.13, 21.0.5, and 22.2.0, the Two-Factor Authentication wasn't enforced for pages marked as public. Any page marked as `@PublicPage` could thus be accessed with a valid user session that isn't authenticated. This particularly affects the Nextcloud Talk application, as this could be leveraged to gain access to any private chat channel without going through the Two-Factor flow. It is recommended that the Nextcloud Server be upgraded to 20.0.13, 21.0.5 or 22.2.0. There are no known workarounds aside from upgrading.

Nextcloud es una plataforma de productividad de código abierto y auto-alojada. Nextcloud Server versiones 20.0.13, 21.0.5 y 22.2.0, la autenticación de dos factores no se aplicaba a las páginas marcadas como públicas. Por lo tanto, se podía acceder a cualquier página marcada como "@PublicPage" con una sesión de usuario válida que no estuviera autenticada. Esto afecta especialmente a la aplicación Nextcloud Talk, ya que podría aprovecharse para acceder a cualquier canal de chat privado sin pasar por el flujo de dos factores. Es recomendado actualizar el servidor Nextcloud a la versión 20.0.13, 21.0.5 o 22.2.0. No se presentan soluciones conocidas aparte de la actualización

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
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
  • 2021-10-25 CVE Published
  • 2023-05-18 EPSS Updated
  • 2024-08-04 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-304: Missing Critical Step in Authentication
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Nextcloud
Search vendor "Nextcloud"
 Server
Search vendor "Nextcloud" for product "Server"
 >= 20.0.3 < 20.0.13
Search vendor "Nextcloud" for product "Server" and version " >= 20.0.3 < 20.0.13"
-
Affected
Nextcloud
Search vendor "Nextcloud"
 Server
Search vendor "Nextcloud" for product "Server"
 >= 21.0.1 < 21.0.5
Search vendor "Nextcloud" for product "Server" and version " >= 21.0.1 < 21.0.5"
-
Affected
Nextcloud
Search vendor "Nextcloud"
 Server
Search vendor "Nextcloud" for product "Server"
 >= 22.1.1 < 22.2.0
Search vendor "Nextcloud" for product "Server" and version " >= 22.1.1 < 22.2.0"
-
Affected