CVE-2026-45283 MEDIUM

CVE-2026-45283: Nextcloud: Files Lock app allows users to lock and unlock files of other users

Vendor Nextcloud
Product security-advisories
Weakness CWE-287 · Improper authentication
Published June 1, 2026
Last update June 1, 2026

CVSS base score

6.3/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

What the vulnerability does

01Description

Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.2, and 33.0.0 to before 33.0.1, the files_lock app did not properly validate the ownership of files when processing DAV lock and unlock requests. An authenticated user could lock or unlock files belonging to other users by targeting their absolute WebDAV paths. Additionally, lock tokens were disclosed to unauthorized callers in error responses, allowing attackers to remove token-based locks placed by other users' client applications. It is recommended that the Nextcloud Server is upgraded to 32.0.2 or 33.0.1. It is recommended that the Nextcloud Enterprise Server is upgraded to 31.0.14.4 or 32.0.2 or 33.0.1

Key dates

02Disclosure timeline

June 1, 2026 CVE published
June 1, 2026 Record updated