Nextcloud

File Disclosure & Symlink Attack via Temp Files in Nextcloud 29-31
CVE-2025-47794 - May 16, 2025

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.

Authorization

2FA Skipped via Session Bug in Nextcloud Server <29.0.15
CVE-2025-47790 - May 16, 2025

Nextcloud Server is a self hosted personal cloud system. Nextcloud Server prior to 29.0.15, 30.0.9, and 31.0.3 and Nextcloud Enterprise Server prior to 26.0.13.15, 27.1.11.15, 28.0.14.6, 29.0.15, 30.0.9, and 31.0.3 have a bug with session handling. The bug caused skipping the second factor confirmation after a successful login with the username and password when the server was configured with `remember_login_cookie_lifetime` set to `0`, once the session expired on the page to select the second factor and the page is reloaded. Nextcloud Server 29.0.15, 30.0.9, and 31.0.3 and Nextcloud Enterprise Server is upgraded to 26.0.13.15, 27.1.11.15, 28.0.14.6, 29.0.15, 30.0.9 and 31.0.3 contain a patch. As a workaround, set the `remember_login_cookie_lifetime` in config.php to a value other than `0`, e.g. `900`. Beware that this is only a workaround for new sessions created after the configuration change. System administration can delete affected sessions.

authentification

Nextcloud Server Access Control Bypass Vulnerability
CVE-2024-52514 - November 15, 2024

Nextcloud Server is a self hosted personal cloud system. After a user received a share with some files inside being blocked by the files access control, the user would still be able to copy the intermediate folder inside Nextcloud allowing them to afterwards potentially access the blocked files depending on the user access control rules. It is recommended that the Nextcloud Server is upgraded to 27.1.9, 28.0.5 or 29.0.0 and Nextcloud Enterprise Server is upgraded to 21.0.9.18, 22.2.10.23, 23.0.12.18, 24.0.12.14, 25.0.13.9, 26.0.13.3, 27.1.9, 28.0.5 or 29.0.0.

Authorization

Nextcloud Server: Unauthorized Access to Password-Protected File Attachments
CVE-2024-52513 - November 15, 2024

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.

Information Disclosure

Session Hijack Enables External Storage Changes in Nextcloud 28.0.11
CVE-2024-52518 5.4 - Medium - November 15, 2024

Nextcloud Server is a self hosted personal cloud system. After an attacker got access to the session of a user or administrator, the attacker would be able to create, change or delete external storages without having to confirm the password. It is recommended that the Nextcloud Server is upgraded to 28.0.12, 29.0.9 or 30.0.2.

AuthZ

Nextcloud Server SVG Preview Path Misreference Prior 27.1.10
CVE-2024-52515 - November 15, 2024

Nextcloud Server is a self hosted personal cloud system. After an admin enables the default-disabled SVG preview provider, a malicious user could upload a manipulated SVG file referencing paths. If the file would exist the preview of the SVG would preview the other file instead. It is recommended that the Nextcloud Server is upgraded to 27.1.10, 28.0.6 or 29.0.1 and Nextcloud Enterprise Server is upgraded to 24.0.12.15, 25.0.13.10, 26.0.13.4, 27.1.10, 28.0.6 or 29.0.1.

Use of Incorrectly-Resolved Name or Reference

Nextcloud Server 22.x-24.x Group Removal Shares Not Revoked
CVE-2024-52516 4.3 - Medium - November 15, 2024

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.

Improper Privilege Management

CVE-2024-52517: Nextcloud Credential Leak API (Fixed 28.0.11,29.0.8,30.0.1)
CVE-2024-52517 5.9 - Medium - November 15, 2024

Nextcloud Server is a self hosted personal cloud system. After storing "Global credentials" on the server, the API returns them and adds them into the frontend again, allowing to read them in plain text when an attacker already has access to an active session of a user. 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.

Information Disclosure

Nextcloud Unencrypted Password in Session Memory (v<28.0.12)
CVE-2024-52525 7.5 - High - November 15, 2024

Nextcloud Server is a self hosted personal cloud system. Under certain conditions the password of a user was stored unencrypted in the session data. The session data is encrypted before being saved in the session storage (Redis or disk), but it would allow a malicious process that gains access to the memory of the PHP process, to get access to the cleartext password of the user. It is recommended that the Nextcloud Server is upgraded to 28.0.12, 29.0.9 or 30.0.2.

Cleartext Storage of Sensitive Information

Nextcloud MD5 Hash Collision in Jobs, Fixed in 28.0.10/29.0.7/30.0.0
CVE-2024-52521 5.3 - Medium - November 15, 2024

Nextcloud Server is a self hosted personal cloud system. MD5 hashes were used to check background jobs for their uniqueness. This increased the chances of a background job with arguments falsely being identified as already existing and not be queued for execution. By changing the Hash to SHA256 the probability was heavily decreased. It is recommended that the Nextcloud Server is upgraded to 28.0.10, 29.0.7 or 30.0.0.

Reversible One-Way Hash

CVE-2024-52520: Nextcloud Server < 28.0.10 SSRF via HEAD (Open-Graph)
CVE-2024-52520 - November 15, 2024

Nextcloud Server is a self hosted personal cloud system. Due to a pre-flighted HEAD request, the link reference provider could be tricked into downloading bigger websites than intended, to find open-graph data. It is recommended that the Nextcloud Server is upgraded to 28.0.10 or 29.0.7 and Nextcloud Enterprise Server is upgraded to 27.1.11.8, 28.0.10 or 29.0.7.

Resource Exhaustion

Nextcloud API Credential Leaks in External Storage (before 28.0.12)
CVE-2024-52523 - November 15, 2024

Nextcloud Server is a self hosted personal cloud system. After setting up a user or administrator defined external storage with fixed credentials, the API returns them and adds them into the frontend again, allowing to read them in plain text when an attacker already has access to an active session of a user. It is recommended that the Nextcloud Server is upgraded to 28.0.12, 29.0.9 or 30.0.2 and Nextcloud Enterprise Server is upgraded to 25.0.13.14, 26.0.13.10, 27.1.11.10, 28.0.12, 29.0.9 or 30.0.2.

Information Disclosure

Read-Only Access Lets Restore Old Versions in Nextcloud (Files_Versions)
CVE-2024-37315 4.3 - Medium - June 14, 2024

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.

CVE-2024-37882 Nextcloud Server <26.0.13: Permission Escalation via Reshare
CVE-2024-37882 8.1 - High - June 14, 2024

Nextcloud Server is a self hosted personal cloud system. A recipient of a share with read&share permissions could reshare the item with more permissions. It is recommended that the Nextcloud Server is upgraded to 26.0.13 or 27.1.8 or 28.0.4 and that the Nextcloud Enterprise Server is upgraded to 26.0.13 or 27.1.8 or 28.0.4.

Improper Preservation of Permissions

Nextcloud Serv. Delete Shared File Versions (Pre-26.0.12)
CVE-2024-37884 5.4 - Medium - June 14, 2024

Nextcloud Server is a self hosted personal cloud system. A malicious user was able to send delete requests for old versions of files they only got shared with read permissions. It is recommended that the Nextcloud Server is upgraded to 26.0.12 or 27.1.7 or 28.0.3 and that the Nextcloud Enterprise Server is upgraded to 26.0.12 or 27.1.7 or 28.0.3.

Nextcloud Server 2FA Bypass Pre-26.0.13/27.1.8/28.0.4 (CVE-2024-37313)
CVE-2024-37313 - June 14, 2024

Nextcloud server is a self hosted personal cloud system. Under some circumstance it was possible to bypass the second factor of 2FA after successfully providing the user credentials. It is recommended that the Nextcloud Server is upgraded to 26.0.13, 27.1.8 or 28.0.4 and Nextcloud Enterprise Server is upgraded to 21.0.9.17, 22.2.10.22, 23.0.12.17, 24.0.12.13, 25.0.13.8, 26.0.13, 27.1.8 or 28.0.4.

Nextcloud user_oidc Missing AC on ID4me (Before 3.0.0) ID4me open registration
CVE-2024-37312 6.3 - Medium - June 14, 2024

user_oidc app is an OpenID Connect user backend for Nextcloud. Missing access control on the ID4me endpoint allows an attacker to register an account eventually getting access to data that is available to all registered users. It is recommended that the OpenID Connect user backend is upgraded to 3.0.0 (Nextcloud 20-23), 4.0.0 (Nexcloud 24) or 5.0.0 (Nextcloud 25-28).

Nextcloud User SAML App Uncontrolled Redirect (5.1.4)
CVE-2024-22400 6.1 - Medium - January 18, 2024

Nextcloud User Saml is an app for authenticating Nextcloud users using SAML. In affected versions users can be given a link to the Nextcloud server and end up on a uncontrolled thirdparty server. It is recommended that the User Saml app is upgraded to version 5.1.5, 5.2.5, or 6.0.1. There are no known workarounds for this issue.

Open Redirect

Nextcloud iOS Files app: Unauth Access via Missing 4-digit PIN (before 4.9.2)
CVE-2023-49790 4.3 - Medium - December 22, 2023

The Nextcloud iOS Files app allows users of iOS to interact with Nextcloud, a self-hosted productivity platform. Prior to version 4.9.2, the application can be used without providing the 4 digit PIN code. Nextcloud iOS Files app should be upgraded to 4.9.2 to receive the patch. No known workarounds are available.

authentification

Nextcloud Server 26/27 Workflow Mod/Del via API Bypass (CVE-2023-49791)
CVE-2023-49791 5.4 - Medium - December 22, 2023

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.

authentification

Nextcloud Server CVE-2023-48304: Unauth Birthday Cal Toggle
CVE-2023-48304 4.3 - Medium - November 21, 2023

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 starting in version 22.0.0 and prior to versions 22.2.10.16, 23.0.12.11, 24.0.12.7, 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Enterprise Server, an attacker could enable and disable the birthday calendar for any user on the same server. Nextcloud Server 25.0.11, 26.0.6, and 27.1.0 and Nextcloud Enterprise Server 22.2.10.16, 23.0.12.11, 24.0.12.7, 25.0.11, 26.0.6, and 27.1.0 contain patches for this issue. No known workarounds are available.

Nextcloud Server Circles XSS via link injection pre27.1.3
CVE-2023-48301 5.4 - Medium - November 21, 2023

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 Nextcloud Enterprise Server, an attacker could insert links into circles name that would be opened when clicking the circle name in a search filter. Nextcloud Server and Nextcloud Enterprise Server versions 25.0.13, 26.0.8, and 27.1.3 contain a fix for this issue. As a workaround, disable app circles.

XSS via Ctrl+Shift+V in Nextcloud Server 25.027.1 (fixed 25.0.13/26.0.8/27.1.3)
CVE-2023-48302 5.4 - Medium - November 21, 2023

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 Nextcloud Enterprise Server, when a user is tricked into copy pasting HTML code without markup (Ctrl+Shift+V) the markup will actually render. Nextcloud Server and Nextcloud Enterprise Server versions 25.0.13, 26.0.8, and 27.1.3 contain a fix for this issue. As a workaround, disable app text.

Nextcloud Server ext storage update flaw 25.0.0-27.1.3
CVE-2023-48239 7.1 - High - November 21, 2023

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 OAuth2 Tokens plaintext storage before 25.0.8/26.0.3/27.0.1
CVE-2023-45151 8.8 - High - October 16, 2023

Nextcloud server is an open source home cloud platform. Affected versions of Nextcloud stored OAuth2 tokens in plaintext which allows an attacker who has gained access to the server to potentially elevate their privilege. This issue has been addressed and users are recommended to upgrade their Nextcloud Server to version 25.0.8, 26.0.3 or 27.0.1. There are no known workarounds for this vulnerability.

Cleartext Storage of Sensitive Information

Nextcloud Rate Limit Reset via Memcached (v<27.1.0)
CVE-2023-45148 4.3 - Medium - October 16, 2023

Nextcloud is an open source home cloud server. When Memcached is used as `memcache.distributed` the rate limiting in Nextcloud Server could be reset unexpectedly resetting the rate count earlier than intended. Users are advised to upgrade to versions 25.0.11, 26.0.6 or 27.1.0. Users unable to upgrade should change their config setting `memcache.distributed` to `\OC\Memcache\Redis` and install Redis instead of Memcached.

Improper Restriction of Excessive Authentication Attempts

Nextcloud Server WebDAV API Brute Force (before 25.09/26.04)
CVE-2023-39960 7.5 - High - October 13, 2023

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server starting with 25.0.0 and prior to 25.09 and 26.04; as well as Nextcloud Enterprise Server starting with 22.0.0 and prior to 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, and 26.0.4; missing protection allows an attacker to brute force passwords on the WebDAV API. Nextcloud Server 25.0.9 and 26.0.4 and Nextcloud Enterprise Server 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, and 26.0.4 contain patches for this issue. No known workarounds are available.

Improper Restriction of Excessive Authentication Attempts

Nextcloud is an open-source productivity platform
CVE-2023-28999 6.4 - Medium - April 04, 2023

Nextcloud is an open-source productivity platform. In Nextcloud Desktop client 3.0.0 until 3.8.0, Nextcloud Android app 3.13.0 until 3.25.0, and Nextcloud iOS app 3.0.5 until 4.8.0, a malicious server administrator can gain full access to an end-to-end encrypted folder. They can decrypt files, recover the folder structure and add new files.? This issue is fixed in Nextcloud Desktop 3.8.0, Nextcloud Android 3.25.0, and Nextcloud iOS 4.8.0. No known workarounds are available.

Missing Encryption of Sensitive Data

Nextcloud android is an android app for interfacing with the nextcloud home server ecosystem
CVE-2023-28646 2.4 - Low - March 30, 2023

Nextcloud android is an android app for interfacing with the nextcloud home server ecosystem. In versions from 3.7.0 and before 3.24.1 an attacker that has access to the unlocked physical device can bypass the Nextcloud Android Pin/passcode protection via a thirdparty app. This allows to see meta information like sharer, sharees and activity of files. It is recommended that the Nextcloud Android app is upgraded to 3.24.1. There are no known workarounds for this vulnerability.

Nextcloud iOS is an ios application used to interface with the nextcloud home cloud ecosystem
CVE-2023-28647 6.8 - Medium - March 30, 2023

Nextcloud iOS is an ios application used to interface with the nextcloud home cloud ecosystem. In versions prior to 4.7.0 when an attacker has physical access to an unlocked device, they may enable the integration into the iOS Files app and bypass the Nextcloud pin/password protection and gain access to a users files. It is recommended that the Nextcloud iOS app is upgraded to 4.7.0. There are no known workarounds for this vulnerability.

Nextcloud android is the official Android client for the Nextcloud home server platform
CVE-2022-39210 5.5 - Medium - September 17, 2022

Nextcloud android is the official Android client for the Nextcloud home server platform. Internal paths to the Nextcloud Android app files are not properly protected. As a result access to internal files of the from within the Nextcloud Android app is possible. This may lead to a leak of sensitive information in some cases. It is recommended that the Nextcloud Android app is upgraded to 3.21.0. There are no known workarounds for this issue.

Directory traversal

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform
CVE-2022-29243 4.3 - Medium - May 31, 2022

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Prior to versions 22.2.7 and 23.0.4, missing input-size validation of new session names allows users to create app passwords with long names. These long names are then loaded into memory on usage, resulting in impacted performance. Versions 22.2.7 and 23.0.4 contain a fix for this issue. There are currently no known workarounds available.

Improper Input Validation

Nextcloud Android is the Android client for Nextcloud, a self-hosted productivity platform
CVE-2022-29160 3.3 - Low - May 20, 2022

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.

Insufficient Cleanup

Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform
CVE-2022-24885 2.4 - Low - April 27, 2022

Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. Prior to version 3.19.1, users can bypass a lock on the Nextcloud app on an Android device by repeatedly reopening the app. Version 3.19.1 contains a fix for the problem. There are currently no known workarounds.

authentification

Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform
CVE-2022-24886 3.8 - Low - April 27, 2022

Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. In versions prior to 3.19.0, any application with notification permission can access contacts if Nextcloud has access to Contacts without applying for the Contacts permission itself. Version 3.19.0 contains a fix for this issue. There are currently no known workarounds.

Incorrect Permission Assignment for Critical Resource

Nextcloud text is a collaborative document editing using Markdown built for the nextcloud server
CVE-2021-41233 5.3 - Medium - March 10, 2022

Nextcloud text is a collaborative document editing using Markdown built for the nextcloud server. Due to an issue with the Nextcloud Text application, which is by default shipped with Nextcloud Server, an attacker is able to access the folder names of "File Drop". For successful exploitation an attacker requires knowledge of the sharing link. It is recommended that users upgrade their Nextcloud Server to 20.0.14, 21.0.6 or 22.2.1. Users unable to upgrade should disable the Nextcloud Text application in the application settings.

AuthZ

The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform
CVE-2021-41166 5.3 - Medium - January 26, 2022

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.

Incorrect Default Permissions

The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform
CVE-2021-43863 7.5 - High - January 25, 2022

The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. The Nextcloud Android app uses content providers to manage its data. Prior to version 3.18.1, the providers `FileContentProvider` and `DiskLruImageCacheFileProvider` have security issues (an SQL injection, and an insufficient permission control, respectively) that allow malicious apps in the same device to access Nextcloud's data bypassing the permission control system. Users should upgrade to version 3.18.1 to receive a patch. There are no known workarounds aside from upgrading.

SQL Injection

Nextcloud server is an open source, self hosted personal cloud
CVE-2021-32800 8.1 - High - September 07, 2021

Nextcloud server is an open source, self hosted personal cloud. In affected versions an attacker is able to bypass Two Factor Authentication in Nextcloud. Thus knowledge of a password, or access to a WebAuthN trusted device of a user was sufficient to gain access to an account. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.1.0. There are no workaround for this vulnerability.

Missing Authentication for Critical Function

Nextcloud server is an open source, self hosted personal cloud
CVE-2021-32802 9.8 - Critical - September 07, 2021

Nextcloud server is an open source, self hosted personal cloud. Nextcloud supports rendering image previews for user provided file content. For some image types, the Nextcloud server was invoking a third-party library that wasn't suited for untrusted user-supplied content. There are several security concerns with passing user-generated content to this library, such as Server-Side-Request-Forgery, file disclosure or potentially executing code on the system. The risk depends on your system configuration and the installed library version. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.1.0. These versions do not use this library anymore. As a workaround users may disable previews by setting `enable_previews` to `false` in `config.php`.

Inclusion of Functionality from Untrusted Control Sphere

Nextcloud server is an open source, self hosted personal cloud
CVE-2021-32801 5.5 - Medium - September 07, 2021

Nextcloud server is an open source, self hosted personal cloud. In affected versions logging of exceptions may have resulted in logging potentially sensitive key material for the Nextcloud Encryption-at-Rest functionality. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.1.0. If upgrading is not an option users are advised to disable system logging to resolve this issue until such time that an upgrade can be performed Note that ff you do not use the Encryption-at-Rest functionality of Nextcloud you are not affected by this bug.

Insertion of Sensitive Information into Log File

Nextcloud Text is an open source plaintext editing application which ships with the nextcloud server
CVE-2021-32766 5.3 - Medium - September 07, 2021

Nextcloud Text is an open source plaintext editing application which ships with the nextcloud server. In affected versions the Nextcloud Text application returned different error messages depending on whether a folder existed in a public link share. This is problematic in case the public link share has been created with "Upload Only" privileges. (aka "File Drop"). A link share recipient is not expected to see which folders or files exist in a "File Drop" share. Using this vulnerability an attacker is able to enumerate folders in such a share. Exploitation requires that the attacker has access to a valid affected "File Drop" link share. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.0.1. Users who are unable to upgrade are advised to disable the Nextcloud Text application in the app settings.

Generation of Error Message Containing Sensitive Information

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer
CVE-2021-32728 6.5 - Medium - August 18, 2021

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading.

Improper Certificate Validation

Nextcloud Android Client is the Android client for Nextcloud
CVE-2021-32727 7.5 - High - July 12, 2021

Nextcloud Android Client is the Android client for Nextcloud. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.16.1, the Nextcloud Android client skipped a step that involved the client checking if a private key belonged to a previously downloaded public certificate. If the Nextcloud instance served a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. The vulnerability is patched in version 3.16.1. As a workaround, do not add additional end-to-end encrypted devices to a user account.

Improper Certificate Validation

Nextcloud Android app is the Android client for Nextcloud
CVE-2021-32694 5.5 - Medium - June 17, 2021

Nextcloud Android app is the Android client for Nextcloud. In versions prior to 3.15.1, a malicious application on the same device is possible to crash the Nextcloud Android Client due to an uncaught exception. The vulnerability is patched in version 3.15.1.

Uncaught Exception

Nextcloud Android app is the Android client for Nextcloud
CVE-2021-32695 3.3 - Low - June 17, 2021

Nextcloud Android app is the Android client for Nextcloud. In versions prior to 3.16.1, a malicious app on the same device could have gotten access to the shared preferences of the Nextcloud Android application. This required user-interaction as a victim had to initiate the sharing flow and choose the malicious app. The shared preferences contain some limited private data such as push tokens and the account name. The vulnerability is patched in version 3.16.1.

Nextcloud iOS before 3.4.2 suffers
CVE-2021-22912 6.5 - Medium - June 11, 2021

Nextcloud iOS before 3.4.2 suffers from an information disclosure vulnerability when searches for sharees utilize the lookup server by default instead of only on the local Nextcloud server unless a global search has been explicitly chosen by the user.

Information Disclosure

Nextcloud Mail before 1.9.5 suffers from improper access control due to a missing permission check
CVE-2021-22896 4.3 - Medium - June 11, 2021

Nextcloud Mail before 1.9.5 suffers from improper access control due to a missing permission check allowing other authenticated users to create mail aliases for other users.

AuthZ

Nextcloud Android App (com.nextcloud.client) before v3.16.0 is vulnerable to information disclosure due to searches for sharees being performed by default on the lookup server instead of only using the local Nextcloud server unless a global search has been explicitly chosen by the user.
CVE-2021-22905 6.5 - Medium - June 11, 2021

Nextcloud Android App (com.nextcloud.client) before v3.16.0 is vulnerable to information disclosure due to searches for sharees being performed by default on the lookup server instead of only using the local Nextcloud server unless a global search has been explicitly chosen by the user.

Information Disclosure

Nextcloud Android is the Android client for the Nextcloud open source home cloud system
CVE-2021-32658 4.6 - Medium - June 08, 2021

Nextcloud Android is the Android client for the Nextcloud open source home cloud system. Due to a timeout issue the Android client may not properly clean all sensitive data on account removal. This could include sensitive key material such as the End-to-End encryption keys. It is recommended that the Nextcloud Android App is upgraded to 3.16.1

Improper Removal of Sensitive Information Before Storage or Transfer