// For flags

CVE-2021-41178

File Traversal affecting SVG files on Nextcloud Server

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 versions 20.0.13, 21.0.5, and 22.2.0, a file traversal vulnerability makes an attacker able to download arbitrary SVG images from the host system, including user provided files. This could also be leveraged into a XSS/phishing attack, an attacker could upload a malicious SVG file that mimics the Nextcloud login form and send a specially crafted link to victims. The XSS risk here is mitigated due to the fact that Nextcloud employs a strict Content-Security-Policy disallowing execution of arbitrary JavaScript. 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. Antes de las versiones 20.0.13, 21.0.5 y 22.2.0, una vulnerabilidad de salto de archivos hace que un atacante pueda descargar imágenes SVG arbitrarias del sistema anfitrión, incluyendo archivos proporcionados por el usuario. Esto también podría ser aprovechado en un ataque de tipo XSS/phishing, un atacante podría subir un archivo SVG malicioso que imita el formulario de inicio de sesión de Nextcloud y enviar un enlace especialmente diseñado a las víctimas. El riesgo de un ataque de tipo XSS en este caso está mitigado debido a que Nextcloud emplea una estricta Política de Seguridad de Contenidos que no permite la ejecución de JavaScript arbitrario. 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
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
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
  • 2023-07-15 EPSS Updated
  • 2024-08-04 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-23: Relative Path Traversal
  • CWE-434: Unrestricted Upload of File with Dangerous Type
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