Nextcloud Server is a self hosted personal cloud system. An attacker with read-only access to a file is able to restore older versions of a document when the files_versions app is enabled. It is recommended that the Nextcloud Server is upgraded to 26.0.12, 27.1.7 or 28.0.3 and that the Nextcloud Enterprise Server is upgraded to 23.0.12.16, 24.0.12.12, 25.0.13.6, 26.0.12, 27.1.7 or 28.0.3.

Nextcloud is an open source content collaboration platform. From versions 1.15.0 to before 1.15.4, 1.16.0 to before 1.16.3, 1.17.0 to before 1.17.1, and 1.18.0 to before 1.18.1, a malicious user with access to an end-to-end encrypted files drop link was able to also drop files into other end-to-end encrypted folders of the share owner. Reading and modifying of other files was not possible. This issue has been patched in versions 1.15.4, 1.16.3, 1.17.1, 1.18.1, and 2.0.0-rc.7.

Nextcloud server is an open source personal cloud server. Affected versions were found to be vulnerable to SMTP command injection. The impact varies based on which commands are supported by the backend SMTP server. However, the main risk here is that the attacker can then hijack an already-authenticated SMTP session and run arbitrary SMTP commands as the email user, such as sending emails to other users, changing the FROM user, and so on. As before, this depends on the configuration of the server itself, but newlines should be sanitized to mitigate such arbitrary SMTP command injection. It is recommended that the Nextcloud Server is upgraded to 22.2.8 , 23.0.5 or 24.0.1. There are no known workarounds for this issue.

Notes is a note-taking app for Nextcloud, an open-source cloud platform. Starting in version 4.4.0 and prior to version 4.8.0, when creating a note file with HTML, the content is rendered in the preview instead of the file being offered to download. Nextcloud Notes app version 4.8.0 contains a patch for the issue. No known workarounds are available.

Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Prior to 5.5.3, a stored HTML injection in the Mail app's message list allowed an authenticated user to inject HTML into the email subjects. Javascript was correctly blocked by the content security policy of the Nextcloud Server code.

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, 17.0.14, 18.1.8, 19.1.8, and 20.1.2.

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 by the content security policy of the Nextcloud Server code. This vulnerability is fixed in 5.5.4, 6.0.6, and 7.2.5.

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.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.0.11, and 21.0.3, filenames where not escaped by default in controllers using `DownloadResponse`. When a user-supplied filename was passed unsanitized into a `DownloadResponse`, this could be used to trick users into downloading malicious files with a benign file extension. This would show in UI behaviours where Nextcloud applications would display a benign file extension (e.g. JPEG), but the file will actually be downloaded with an executable file extension. The vulnerability is patched in versions 19.0.13, 20.0.11, and 21.0.3. Administrators of Nextcloud instances do not have a workaround available, but developers of Nextcloud apps may manually escape the file name before passing it into `DownloadResponse`.

A missing access control check in Nextcloud Server < 18.0.1, < 17.0.4, and < 16.0.9 causes hide-download shares to be downloadable when appending /download to the URL.

Improper access control in Nextcloud Deck 0.8.0 allowed an attacker to reshare boards shared with them with more permissions than they had themselves.

Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.9, and 33.0.0 to before 33.0.3, when a malicious user has access to a file share of a user, they could use this share token to also access the chunking upload directly and see temporary part files during on going uploads. It is recommended that the Nextcloud Server is upgraded to 32.0.9 or 33.0.3. It is recommended that the Nextcloud Enterprise Server is upgraded to 26.0.13.26, 27.1.11.25, 28.0.14.17, 29.0.16.16, 30.0.17.9, 31.0.14.5, 32.0.9 or 33.0.3

A bug in Nextcloud Server 14.0.4 could expose more data in reshared link shares than intended by the sharer.

Improper access control in Groupfolders app 4.0.3 allowed to delete hidden directories when when renaming an accessible item to the same name.

Improper access control in Nextcloud Deck 1.0.0 allowed an attacker to inject tasks into other users decks.

A missing check in Nextcloud Server 14.0.3 could give recipient the possibility to extend the expiration date of a share they received.

Improper access control in Nextcloud Social app version 0.3.1 allowed to read posts of any user.

Nextcloud Server is an open source personal cloud server. Prior to versions 24.0.7 and 25.0.1, disabled download shares still allow download through preview images. Images could be downloaded and previews of documents (first page) can be downloaded without being watermarked. Versions 24.0.7 and 25.0.1 contain a fix for this issue. No known workarounds are available.

The Nextcloud Notes app is a distraction free notes taking app for Nextcloud. If an attacker managed to share a folder called `Notes/` with a newly created user before they logged in, the Notes app would use that folder store the personal notes. It is recommended that the Nextcloud Notes app is upgraded to 4.9.3.

Improper revalidation of permissions in Nextcloud Server prior to 14.0.0, 13.0.6 and 12.0.11 lead to not accepting access restrictions by acess tokens.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Nextcloud Server and Nextcloud Enterprise Server prior to versions 23.0.9 and 24.0.5 are vulnerable to exposure of information that cannot be controlled by administrators without direct database access. Versions 23.0.9 and 24.0.5 contains patches for this issue. No known workarounds are available.

Nextcloud is an open source content collaboration platform. From version 2.6.0 to before version 4.3.0, when a previous collective pages was deleted and the collective was shared view-only, guests with access to the collective were able to access the deleted pages directly from the trashbin. This issue has been patched in version 4.3.0.

Nextcloud is an open source content collaboration platform. From version 1.3.6 to before version 8.4.0, an improper check allowed users that where provided by LDAP to still authenticate towards user OIDC after they where deleted. This issue has been patched in version 8.4.0.

Nextcloud is an open source content collaboration platform. From versions 17.0.0 to before 17.0.15, 18.0.0 to before 18.1.12, 19.0.0 to before 19.1.16, 20.0.0 to before 20.1.11, and 21.0.0 to before 21.0.4, a user with READ and CREATE permission, but no UPDATE permission for a team folder can rename files in the team folder. This issue has been patched in versions 17.0.15, 18.1.12, 19.1.16, 20.1.11, and 21.0.4.

Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.9, and 33.0.0 to before 33.0.3, an authenticated attacker can access attachments of link shares when knowing the share token, circumventing password protection or download restrictions. It is applicable to any file that is shared directly, as the attacker only needs to know a documentId they own, apart of the mentioned share token. For shared folders the attacker has to know or guess a documentId of a file that is included inside the folder, making it much harder to exploit. The attacker can only extract an attachments, but not the file shared file or folder itself. It is recommended that the Nextcloud Server is upgraded to 33.0.3 or 32.0.9. It is recommended that the Nextcloud Enterprise Server is upgraded to 33.0.3, 32.0.9, 31.0.14.5, 30.0.17.9, 29.0.16.16, 28.0.14.17 or 27.1.11.5

Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. A user with access to a deck board was able to access comments and attachments of already deleted cards. It is recommended that the Nextcloud Deck app is upgraded to 1.6.6 or 1.7.5 or 1.8.7 or 1.9.6 or 1.11.3 or 1.12.1.

richdocuments is the repository for NextCloud Collabra, the app for Nextcloud Office collaboration. Prior to versions 6.0.0, 5.0.4, and 4.2.6, a user could be tricked into working against a remote Office by sending them a federated share. richdocuments versions 6.0.0, 5.0.4 and 4.2.6 contain a fix for this issue. There are currently no known workarounds available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server prior to versions 26.0.9 and 27.1.4; as well as Nextcloud Enterprise Server prior to versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4; when an attacker manages to get access to an active session of another user via another way, they could delete and modify workflows by sending calls directly to the API bypassing the password confirmation shown in the UI. Nextcloud Server versions 26.0.9 and 27.1.4 and Nextcloud Enterprise Server versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Server and Nextcloud Enterprise Server, admins can change authentication details of user configured external storage. Nextcloud Server and Nextcloud Enterprise Server versions 25.0.11, 26.0.6, and 27.1.0 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.13, 26.0.8, and 27.1.3 of Nextcloud Server and starting in version 20.0.0 and prior to versions 20.0.14.16, 21.0.9.13, 22.2.10.15, 23.0.12.12, 24.0.12.8, 25.0.13, 26.0.8, and 27.1.3 of Nextcloud Enterprise Server, a malicious user could update any personal or global external storage, making them inaccessible for everyone else as well. Nextcloud Server 25.0.13, 26.0.8, and 27.1.3 and Nextcloud Enterprise Server is upgraded to 20.0.14.16, 21.0.9.13, 22.2.10.15, 23.0.12.12, 24.0.12.8, 25.0.13, 26.0.8, and 27.1.3 contain a patch for this issue. As a workaround, disable app files_external. This workaround also makes the external storage inaccessible but retains the configurations until a patched version has been deployed.

Nextcloud Android is the Android client for Nextcloud, a self-hosted productivity platform. Prior to version 3.19.0, sensitive tokens, images, and user related details exist after deletion of a user account. This could result in misuse of the former account holder's information. Nextcloud Android version 3.19.0 contains a patch for this issue. There are no known workarounds available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.9, 26.0.4, and 27.0.1, unauthenticated users could send a DAV request which reveals whether a calendar or an address book with the given identifier exists for the victim. Nextcloud Server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 24.0.4 and prior to versions 25.0.9, 26.0.4, and 27.0.1, when a folder with images or an image was shared without download permissions, the user could add the image inline into a text file and download it. Nextcloud Server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 22.0.0 and prior to versions 22.2.10.13, 23.0.12.8, 24.0.12.4, 25.0.8, 26.0.3, and 27.0.1, a user can access files inside a subfolder of a groupfolder accessible to them, even if advanced permissions would block access to the subfolder. Nextcloud Server versions 25.0.8, 26.0.3, and 27.0.1 and Nextcloud Enterprise Server versions 22.2.10.13, 23.0.12.8, 24.0.12.4, 25.0.8, 26.0.3, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 20.0.0 and prior to versions 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1, a missing password confirmation allowed an attacker, after successfully stealing a session from a logged in user, to create app passwords for the victim. Nextcloud server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 19.0.0 and prior to versions 19.0.13.10, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1, a malicious user could delete any personal or global external storage, making them inaccessible for everyone else as well. Nextcloud server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 19.0.13.10, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. As a workaround, disable app files_external. This also makes the external storage inaccessible but retains the configurations until a patched version has been deployed.

Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Prior to 1.14.6 and 1.15.2, a bug in the permission logic allowed users with "Can share" permission to modify the permissions of other recipients. This vulnerability is fixed in 1.14.6 and 1.15.2.

Nextcloud Server before 9.0.54 and 10.0.1 & ownCloud Server before 9.0.6 and 9.1.2 suffer from content spoofing in the dav app. The exception message displayed on the DAV endpoints contained partially user-controllable input leading to a potential misrepresentation of information.

Nextcloud Server before 9.0.54 and 10.0.1 & ownCloud Server before 9.0.6 and 9.1.2 suffer from content spoofing in the files app. The location bar in the files app was not verifying the passed parameters. An attacker could craft an invalid link to a fake directory structure and use this to display an attacker-controlled error message to the user.

Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. The Nextcloud mail app incorrectly allowed attaching shared files without download permissions as attachments. This allowed users to send them the files to themselves and then downloading it from their mail clients. It is recommended that the Nextcloud Mail is upgraded to 2.2.10, 3.6.2 or 3.7.2.

Nextcloud Desktop is the desktop sync client for Nextcloud. In versions of Nextcloud Desktop prior to 3.15, 3rdparty applications already installed on a user machine can create link shares for almost all data via the socket API. These shares can then be easily sent off to an external service. Nextcloud Desktop fixes the issue in version 3.15. No known workarounds are available.

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server prior to 29.0.13, 30.0.7, and 31.0.1 and Nextcloud Enterprise Server prior to 26.0.13.13, 27.1.11.13, 28.0.14.4, 29.0.13, 30.0.7, and 31.0.1, an attacker on a multi-user system may read temporary files from Nextcloud running with a different user account, or run a symlink attack. Nextcloud Server versions 29.0.13, 30.0.7, and 31.0.1 and Nextcloud Enterprise Server 26.0.13.13, 27.1.11.13, 28.0.14.4, 29.0.13, 30.0.7, and 31.0.1 fix the issue. No known workarounds are available.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are not properly verifying edit check permissions on WebDAV copy actions. The WebDAV endpoint was not properly checking the permission on a WebDAV COPY action. This allowed an authenticated attacker with access to a read-only share to put new files in there. It was not possible to modify existing files.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are vulnerable to a content-spoofing attack in the files app. The location bar in the files app was not verifying the passed parameters. An attacker could craft an invalid link to a fake directory structure and use this to display an attacker-controlled error message to the user.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are not properly verifying restore privileges when restoring a file. The restore capability of Nextcloud/ownCloud was not verifying whether a user has only read-only access to a share. Thus a user with read-only access was able to restore old versions.

Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the "Add server automatically once a federated share was created successfully" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable "Add server automatically once a federated share was created successfully" in the Nextcloud settings.

Bypass lock protection in the Nextcloud Android app prior to version 3.6.2 causes leaking of thumbnails when requesting the Android content provider although the lock protection was not solved.

Nextcloud Mail is a mail app for the Nextcloud platform. A missing permission check in Nextcloud Mail before 1.4.3 and 1.8.2 allows another authenticated users to access mail metadata of other users. Versions 1.4.3 and 1.8.2 contain patches for this vulnerability; no workarounds other than the patches are known to exist.

A missing user check in Nextcloud prior to 20.0.6 inadvertently populates a user's own credentials for other users external storage configuration when not already configured yet.

A wrong check for the system time in the Android App 3.9.0 causes a bypass of the lock protection when changing the time of the system to the past.