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.

Nextcloud Server before 9.0.55 and 10.0.2 suffers from a error message disclosing existence of file in write-only share. Due to an error in the application logic an adversary with access to a write-only share may enumerate the names of existing files and subfolders by comparing the exception messages.

Nextcloud Talk is an open source chat, video & audio calls client for the Nextcloud platform. In affected versions an attacker could see the last video frame of any participant who has video disabled but a camera selected. It is recommended that the Nextcloud Talk app is upgraded to 13.0.8 or 14.0.4. Users unable to upgrade should select "None" as camera before joining the call.

Nextcloud is an open source content collaboration platform. From version 0.8.0 to before version 1.0.4, the view filter criteria is exposed to users with read-only permissions in Nextcloud Tables. This issue has been patched in versions 1.0.4 and 2.0.0.

Nextcloud files Zip app is a tool to create zip archives from one or multiple files from within Nextcloud. In affected versions users can download "view-only" files by zipping the complete folder. It is recommended that the Files ZIP app is upgraded to 1.2.1, 1.4.1, or 1.5.0. Users unable to upgrade should disable the file zip app.

Nextcloud Deck is a Kanban-style project & personal management tool for Nextcloud, similar to Trello. The full path of the application is exposed to unauthorized users. It is recommended that the Nextcloud Deck app is upgraded to 1.2.11, 1.4.6, or 1.5.4. There is no workaround available.

Nextcloud is an open source content collaboration platform. From versions 5.5.13 to before 5.5.17, and 6.2.0 to before 6.2.3, an authenticated user can enumerate users on the same Nextcloud instance by using the Calendar app's endpoint for suggesting attendees. The sharing restrictions, applied to other endpoints, were not effective here. This issue has been patched in versions 5.5.17 and 6.2.3.

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. In Nextcloud Server from versions 32.0.0 to before 32.0.7 and 33.0.0 to before 33.0.1, a missing access check on API level allowed to add unknown circles by their ID directly to other circles. Since circle IDs have 62^15 complexity by default this is still unlikely to be executable at will, but if access to an ID was available via another source, memberships could be tracked like this. It is recommended that the Nextcloud Server is upgraded to 32.0.7 or 33.0.1. It is recommended that the Nextcloud Enterprise Server is upgraded to 29.0.16.14, 30.0.17.8, 31.0.14.3, 32.0.7 or 33.0.1

The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. An issue in versions prior to 3.17.1 may lead to sensitive information disclosure. An unauthorized app that does not have the otherwise required `MANAGE_DOCUMENTS` permission may view image thumbnails for images it does not have permission to view. Version 3.17.1 contains a patch. There are no known workarounds.

Nextcloud Richdocuments in an open source self hosted online office. Nextcloud uses the WOPI ("Web Application Open Platform Interface") protocol to communicate with the Collabora Editor, the communication between these two services was not protected by a credentials or IP check. Whilst this does not result in gaining access to data that the user has not yet access to, it can result in a bypass of any enforced watermark on documents as described on the [Nextcloud Virtual Data Room](https://nextcloud.com/virtual-data-room/) website and [our documentation](https://portal.nextcloud.com/article/nextcloud-and-virtual-data-room-configuration-59.html). The Nextcloud Richdocuments releases 3.8.3 and 4.2.0 add an additional admin settings for an allowlist of IP addresses that can access the WOPI API. We recommend upgrading and configuring the allowlist to a list of Collabora servers. There is no known workaround. Note that this primarily results a bypass of any configured watermark or download protection using File Access Control. If you do not require or rely on these as a security feature no immediate action is required on your end.

Nextcloud Tables allows you to create your own tables with individual columns. Prior to 0.8.7 and 0.9.4, authenticated users were able to view meta data of columns in other tables of the Tables app by modifying the numeric ID in a request. This vulnerability is fixed in 0.8.7 and 0.9.4.

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.

Nextcloud Deck before 1.0.2 suffers from an insecure direct object reference (IDOR) vulnerability that permits users with a duplicate user identifier to access deck data of a previous deleted user.

Missing access control in Nextcloud Deck 1.0.4 caused an insecure direct object reference allowing an attacker to view all attachments.

Improper preservation of permissions in Nextcloud Server 14.0.3 causes the event details to be leaked when sharing a non-public event.

Improper authorization in the Circles app 0.17.7 causes retaining access when an email address was removed from a circle.

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.

Nextcloud Server 30.0.0 is vulnerable to an Insecure Direct Object Reference (IDOR) in the /core/preview endpoint. Any authenticated user can access previews of arbitrary files belonging to other users by manipulating the fileId parameter. This allows unauthorized disclosure of sensitive data, such as text files or images, without prior sharing permissions.

Nextcloud Mail is a mail app for Nextcloud. In versions prior to 1.9.6, the Nextcloud Mail application does not, by default, render images in emails to not leak the read state. The privacy filter failed to filter images with a `background-image` CSS attribute. Note that the images were still passed through the Nextcloud image proxy, and thus there was no IP leakage. The issue was patched in version 1.9.6 and 1.10.0. No workarounds are known to exist.

A missing check in the Nextcloud Server prior to version 15.0.1 causes leaking of calendar event names when adding or modifying confidential or private events.

Nextcloud talk is a chat module for the Nextcloud server platform. In affected versions brute force protection of public talk conversation passwords can be bypassed, as there was an endpoint validating the conversation password without registering bruteforce attempts. It is recommended that the Nextcloud Talk app is upgraded to 15.0.8, 16.0.6 or 17.1.1. There are no known workarounds for this vulnerability.

Improper authorization in Nextcloud server 17.0.0 causes leaking of previews and files when a file-drop share link is opened via the gallery app.

Calendar app for Nextcloud easily sync events from various devices with your Nextcloud. Some internal paths of the website are disclosed when the SMTP server is unavailable. It is recommended that the Calendar app is updated to 3.5.5 or 4.2.3

Nextcloud Talk is a chat, video & audio call extension for Nextcloud. In affected versions a user that was added later to a conversation can use this information to get access to data that was deleted before they were added to the conversation. This issue has been patched in version 15.0.5 and it is recommended that users upgrad to 15.0.5. There are no known workarounds for this issue.

Nextcloud Server is an open source personal cloud server. Nextcloud Server 24.0.0 until 24.0.6 and 25.0.0 until 25.0.4, as well as Nextcloud Enterprise Server 23.0.0 until 23.0.11, 24.0.0 until 24.0.6, and 25.0.0 until 25.0.4, have an information disclosure vulnerability. A user was able to get the full data directory path of the Nextcloud server from an API endpoint. By itself this information is not problematic as it can also be guessed for most common setups, but it could speed up other unknown attacks in the future if the information is known. Nextcloud Server 24.0.6 and 25.0.4 and Nextcloud Enterprise Server 23.0.11, 24.0.6, and 25.0.4 contain patches for this issue. There are no known workarounds.

Nextcloud Server is a self hosted personal cloud system. When a server is configured to only allow sharing with users that are in ones own groups, after a user was removed from a group, previously shared items were not unshared. It is recommended that the Nextcloud Server is upgraded to 22.2.11 or 23.0.11 or 24.0.6 and Nextcloud Enterprise Server is upgraded to 22.2.11 or 23.0.11 or 24.0.6.

Nextcloud Server is a self hosted personal cloud system. After receiving a "Files drop" or "Password protected" share link a malicious user was able to download attachments that are referenced in Text files without providing the password. It is recommended that the Nextcloud Server is upgraded to 28.0.11, 29.0.8 or 30.0.1 and Nextcloud Enterprise Server is upgraded to 25.0.13.13, 26.0.13.9, 27.1.11.9, 28.0.11, 29.0.8 or 30.0.1.

Nextcloud Server before 12.0.8 and 13.0.3 suffers from improper checks of dropped permissions for incoming shares allowing a user to still request previews for files it should not have access to.

user_oidc is an OpenID Connect user backend for Nextcloud. In versions prior to 1.2.1 sensitive information such as the OIDC client credentials and tokens are sent in plain text of HTTP without TLS. Any malicious actor with access to monitor user traffic may have been able to compromise account security. This issue has been addressed in in user_oidc v1.2.1. Users are advised to upgrade. Users unable to upgrade may use https to access Nextcloud. Set an HTTPS discovery URL in the provider settings (in Nextcloud OIDC admin settings).

Nextcloud files access control is a nextcloud app to manage access control for files. Users with limited access can see file names in certain cases where they do not have privilege to do so. This issue has been addressed and it is recommended that the Nextcloud Files Access Control app is upgraded to 1.12.2, 1.13.1 or 1.14.1. There are no known workarounds for this issue

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Prior to versions 22.2.6 and 23.0.3, a user can create a link that is not password protected even if the administrator requires links to be password protected. Versions 22.2.6 and 23.0.3 contain a patch for this issue. There are currently no known workarounds.

Nextcloud server is a self hosted system designed to provide cloud style services. The groupfolders application for Nextcloud allows sharing a folder with a group of people. In addition, it allows setting "advanced permissions" on subfolders, for example, a user could be granted access to the groupfolder but not specific subfolders. Due to a lacking permission check in affected versions, a user could still access these subfolders by copying the groupfolder to another location. It is recommended that the Nextcloud Server is upgraded to 20.0.14, 21.0.6 or 22.2.1. Users unable to upgrade should disable the "groupfolders" application in the admin settings.

Nextcould Talk android is a video and audio conferencing app for Nextcloud. Prior to versions 12.2.8, 13.0.10, 14.0.6, and 15.0.0, guests can continue to receive video streams from a call after being removed from a conversation. An attacker would be able to see videos on a call in a public conversation after being removed from that conversation, provided that they were removed while being in the call. Versions 12.2.8, 13.0.10, 14.0.6, and 15.0.0 contain patches for the issue. No known workarounds are available.

Nextcloud Talk is a video and audio conferencing app for Nextcloud. Prior to versions 12.2.7, 13.0.7, and 14.0.3, password protected conversations are susceptible to brute force attacks if the attacker has the link/conversation token. It is recommended that the Nextcloud Talk application is upgraded to 12.2.7, 13.0.7 or 14.0.3. There are currently no known workarounds available apart from not having password protected conversations.

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server prior to 31.0.10 and 32.0.1 and Nextcloud Enterprise Server prior to 28.0.14.11, 29.0.16.8, 30.0.17.3, and 31.0.10, contacts search allowed to retrieve personal data of other users (emails, names, identifiers) without proper access control. This allows an authenticated user to retrieve information about accounts that are not related or added as contacts.

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

Exposure of Private Information in Nextcloud Server 16.0.1 causes the server to send it's domain and user IDs to the Nextcloud Lookup Server without any further data when the Lookup server is disabled.

Nextcloud Talk is a video and audio conferencing app for Nextcloud. In versions prior to 13.0.5 and 14.0.0, a call moderator can indirectly enable user webcams by granting permissions, if they were enabled before removing the permissions. A patch is available in versions 13.0.5 and 14.0.0. There are currently no known workarounds.

The Document Embedder WordPress plugin before 1.7.9 contains a AJAX action endpoint, which could allow any authenticated user, such as subscriber to enumerate the title of arbitrary private and draft posts.

HashiCorp Nomad and Nomad Enterprise 1.4.0 up to 1.4.1 workload identity token can list non-sensitive metadata for paths under nomad/ that belong to other jobs in the same namespace. Fixed in 1.4.2.

Due to missing authorization checks, SAP Business Warehouse (BEx Analyzer) allows an authenticated attacker to access information over the network which is otherwise restricted. On successful exploitation the attacker can enumerate information causing a limited impact on confidentiality of the application.

An access control issue in Zammad v5.0.3 broadcasts administrative configuration changes to all users who have an active application instance, including settings that should only be visible to authenticated users.

Due to missing authorization checks, SAP BEx Analyzer allows an authenticated attacker to access information over the network which is otherwise restricted. On successful exploitation the attacker can enumerate information causing a limited impact on confidentiality of the application.

When creating or updating credentials for single-user access, Apache NiFi wrote a copy of the Login Identity Providers configuration to the operating system temporary directory. On most platforms, the operating system temporary directory has global read permissions. NiFi immediately moved the temporary file to the final configuration directory, which significantly limited the window of opportunity for access. NiFi 1.16.0 includes updates to replace the Login Identity Providers configuration without writing a file to the operating system temporary directory.

OpenEMR v6.0.0 was discovered to contain an incorrect access control issue.

OpenClaw before 2026.4.26 contains an information disclosure vulnerability in sandboxed session spawning that exposes the real workspace path to child prompts. Attackers can exploit this by spawning child sessions from sandboxed parents to reveal host workspace location or related memory context to child models.

An issue has been discovered in GitLab CE/EE affecting all versions from 17.1 before 17.10.7, 17.11 before 17.11.3, and 18.0 before 18.0.1. Under certain conditions un-authorised users can view full email addresses that should be partially obscured.

Discourse is an open source discussion platform. In versions prior to 2.7.7 there are two bugs which led to the post creator of a whisper post being revealed to non-staff users. 1: Staff users that creates a whisper post in a personal message is revealed to non-staff participants of the personal message even though the whisper post cannot be seen by them. 2: When a whisper post is before the last post in a post stream, deleting the last post will result in the creator of the whisper post to be revealed to non-staff users as the last poster of the topic.

An issue was discovered in the VisualEditor extension in MediaWiki before 1.31.13, and 1.32.x through 1.35.x before 1.35.2. . When using VisualEditor to edit a MediaWiki user page belonging to an existing, but hidden, user, VisualEditor will disclose that the user exists. (It shouldn't because they are hidden.) This is related to ApiVisualEditor.