Vulnerability in Nextcloud Desktop
CVE-2021-37617
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.005 (37.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 37.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: -0.000
Affected products
- Nextcloud Desktop
- Nextcloud Security-Advisories — versions >= 3.0.3 , <= 3.2.4
Weakness classification (CWE)
References
- github.com/nextcloud/security-advisories/security/advisories/GHSA-6q2w-v879-q24v (Third Party Advisory)
- github.com/nextcloud/desktop/pull/3497 (Patch, Third Party Advisory)
- hackerone.com/reports/1240749 (Permissions Required, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-37617?
- CVE-2021-37617 is a high-severity vulnerability in Nextcloud Desktop, classified under Untrusted Search Path. CVSS score: 7.3/10. Published 2021-08-18.
- How severe is CVE-2021-37617?
- High severity. CVSS v3 base score is 7.3 out of 10.