CVE-2021-37617

Publication date 18 August 2021

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. The Nextcloud Desktop Client invokes its uninstaller script when being installed to make sure there are no remnants of previous installations. In versions 3.0.3 through 3.2.4, the Client searches the `Uninstall.exe` file in a folder that can be written by regular users. This could lead to a case where a malicious user creates a malicious `Uninstall.exe`, which would be executed with administrative privileges on the Nextcloud Desktop Client installation. This issue is fixed in Nextcloud Desktop Client version 3.3.0. As a workaround, do not allow untrusted users to create content in the `C:\` system folder and verify that there is no malicious `C:\Uninstall.exe` file on the system.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
nextcloud-desktop	22.04 LTS jammy	Not affected
	21.10 impish	Not affected
	21.04 hirsute	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Ignored end of standard support
	14.04 LTS trusty	Not in release

Notes

seth-arnold

Windows-specific

Severity score breakdown

Parameter	Value
Base score	7.3 · High
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	Required
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H