CVE-2025-66511: Use of Insufficiently Random Values

Nextcloud Calendar is a calendar app for Nextcloud. Prior to 6.0.3, the Calendar app generates participant tokens for meeting proposals using a hash function, allowing an attacker to compute valid participant tokens, which allowed them to request details and submit dates in meeting proposals. The...

CVE-2025-66545: Improper Neutralization

Nextcloud Groupfolders provides admin-configured folders shared by everyone in a group or team. Prior to 14.0.11, 15.3.12, 16.0.15, 17.0.14, 18.1.8, 19.1.8, and 20.1.2, a user with read-only permission can restore a file from the trash bin. This vulnerability is fixed in 14.0.11, 15.3.12, 16.0.15...

CVE-2025-66547: Authorization Bypass Through User-Controlled Key

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Enterprise Server prior to 31.0.1, non-privileged users can modify tags on files they should not have access to via bulk tagging. This vulnerability is fixed in 31.0.1...

CVE-2025-66550: Improper Handling of Unexpected Data Type

Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.17 and 5.2.4, when a malicious user creates a calendar event with a crafted attachment that links to a download link of a file on the same Nextcloud server, the file would be downloaded without the user confirming the action. This...

CVE-2025-66551: Authorization Bypass Through User-Controlled Key

Nextcloud Tables allows you to create your own tables with individual columns. Prior to 0.8.6 and 0.9.3, a malicious user was able to create their own table and then move a column to a victims table. This vulnerability is fixed in 0.8.6 and 0.9.3...

WebAuthn second factor provider for Nextcloud 安全漏洞

WebAuthn second factor provider for Nextcloud is an open source two-factor authentication software from Nextcloud. A security vulnerability exists in WebAuthn second factor provider for Nextcloud versions prior to 1.4.2 and prior to 2.4.1, which stems from a lack of ownership checking and could...

Nextcloud 跨站脚本漏洞

Nextcloud is an open source suite of self-hosted file synchronization and sharing communication application platform from Nextcloud, Germany. A cross-site scripting vulnerability exists in Nextcloud versions prior to 5.5.4, prior to 6.0.6, and prior to 7.2.5, which stems from a malicious user bei...

Nextcloud Tables 安全漏洞

Nextcloud Tables is an open source tables application from Nextcloud. A security vulnerability exists in Nextcloud Tables versions prior to 0.8.7 and prior to 0.9.4, which stems from an authenticated user being able to view metadata of other forms, potentially leading to information disclosure...

Nextcloud Mail 跨站脚本漏洞

Nextcloud Mail is an email from Nextcloud Germany. A cross-site scripting vulnerability exists in versions of Nextcloud Mail prior to 5.5.3, which stems from the presence of stored HTML injection in mailing lists, which could lead to HTML injection attacks...

Nextcloud Tables 安全漏洞

Nextcloud Tables is an open source tables application from Nextcloud. A security vulnerability exists in Nextcloud Tables versions prior to 0.8.9, prior to 0.9.6, and prior to 1.0.1, which stems from shared table information that is not restricted from access by privileged users, which could lead...

PT-2025-49289

Name of the Vulnerable Software and Affected Versions Nextcloud Calendar versions prior to 4.7.19 Nextcloud Calendar versions prior to 5.5.6 Nextcloud Calendar versions prior to 6.0.1 Description The Nextcloud Calendar application contained a flaw where appointments could be booked without knowin...

PT-2025-49300

Name of the Vulnerable Software and Affected Versions Nextcloud Contacts app versions prior to 5.5.4 Nextcloud Contacts app versions prior to 6.0.6 Nextcloud Contacts app versions prior to 7.2.5 Description A malicious user could modify the organisation and title fields to load additional CSS...

PT-2025-49266

Name of the Vulnerable Software and Affected Versions Nextcloud Calendar versions prior to 6.0.3 Description The Calendar application for Nextcloud generates participant tokens for meeting proposals using a predictable hash function. This allows an attacker to compute valid tokens, potentially...

PT-2025-49288

Name of the Vulnerable Software and Affected Versions Nextcloud Tables versions prior to 0.8.9 Nextcloud Tables versions prior to 0.9.6 Nextcloud Tables versions prior to 1.0.1 Description Nextcloud Tables allows users to create custom tables with defined columns. Before versions 0.8.9, 0.9.6, an...

CVE-2025-66512: Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Server Enterprise prior to 31.0.12 and 32.0.3, a missing sanitization allowed malicious users to circumvent the content security policy when a malicious user manages to trick a user it viewing an uploaded SVG outside...

CVE-2025-66515: Improper Authentication

The Nextcloud Approval app allows approval or disapproval of files in the sidebar. Prior to 1.3.1 and 2.5.0, an authenticated user listed as a requester in a workflow can set another user’s file into the “pending approval” without access to the file by using the numeric file id. This vulnerabilit...

CVE-2025-66549: Generation of Error Message Containing Sensitive Information

Nextcloud Desktop is the desktop sync client for Nextcloud. Prior to 3.16.5, when trying to manually lock a file inside an end-to-end encrypted directory, the path of the file was sent to the server unencrypted, making it possible for administrators to see it in log files. This vulnerability is...

CVE-2025-66554: Improper Neutralization of Input During Web Page Generation

Contacts app for Nextcloud easily syncs contacts from various devices with your Nextcloud and allows editing. Prior to 5.5.4, 6.0.6, and 7.2.5, a malicious user was able to modify their organisation and title field to load additional CSS files. Javascript and other options were correctly blocked ...

CVE-2025-66546: Authorization Bypass Through User-Controlled Key

Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.19, 5.5.6, and 6.0.1, the calendar app allowed blindly booking appointments with a squential ID without known the appointment token. This vulnerability is fixed in 4.7.19, 5.5.6, and 6.0.1...

CVE-2025-66556: Authorization Bypass Through User-Controlled Key

Nextcloud talk is a video & audio conferencing app for Nextcloud. Prior to 20.1.8 and 21.1.2, a participant with chat permissions was able to delete poll drafts of other participants within the conversation based on their numeric ID. This vulnerability is fixed in 20.1.8 and 21.1.2...