Nextcloud vulnerabilities
We track 49 vulnerabilities in Nextcloud products across 16 products. 49 are rated high or critical, and none are known to be exploited. The most recent was published on October 27, 2026.
Latest Nextcloud vulnerabilities
- 7.5 High severity
server: Uncontrolled Resource Consumption
Abusing the federated share endpoint, an attacker can write arbitrary rows into the oc_share_external database table. These rows persist indefinitely — there is no automatic cleanup mechanism. Three distinct denial-of-service conditions follow from this write
- 7.1 High severity
security-advisories: Improper Neutralization of Special Elements used in an SQL Command
Nextcloud is an open source content collaboration platform. From versions 0.9.0 to before 0.9.7, and 1.0.0 to before 1.0.2, a missing sanitization in the Tables app allowed a user with access to the tables app to perform a limited SQL injection in the ORDER BY
- 8.2 High severity
security-advisories: Improper Neutralization of Special Elements used in an SQL Command
Nextcloud is an open source content collaboration platform. From versions 0.7.0 to before 0.7.7, 0.8.0 to before 0.8.10, 0.9.0 to before 0.9.8, and 1.0.0 to before 1.0.4, an authenticated attacker with access to the Tables app may be able to execute arbitrary
- 8.8 High severity
security-advisories: Improper Access Control
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
- 8.1 High severity
security-advisories: Authorization Bypass Through User-Controlled Key
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, with the knowledge of other users’ principal URL an attacker could possibly send a request to gain full access t
- 8.1 High severity
security-advisories: Improper Authentication
Nextcloud is an open source content collaboration platform. From versions 0.3.0 to before 3.1.0, 5.0.0 to before 5.1.0, and 6.0.0 to before 6.4.0, a missing signature verification in User OIDC allowed a malicious ID4me authority to identify as any user. This i
- 8.8 High severity
Windmill CE (Community Edition): Missing Authorization
Windmill versions 1.56.0 through 1.614.0 contain a missing authorization vulnerability that allows users with the Operator role to perform prohibited entity creation and modification actions via the backend API. Although Operators are documented and priced as
- 7.5 High severity
security-advisories: Improper Certificate Validation
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with your computer. The Desktop client did not stop with an error but allowed by-passing the signature validation, if a manipulated server sends an empty initial signature. It is
- 8.1 High severity
security-advisories: Exposure of Sensitive Information to an Unauthorized Actor
Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. When a user is trying to set up a mail account with an email address like [email protected] that does not support auto configuration, and an attacker managed to register autoconf
- 7.5 High severity
security-advisories: Cleartext Storage of Sensitive Information
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 m
- 8.2 High severity
security-advisories: Insecure Storage of Sensitive Information
Nextcloud Server is a self hosted personal cloud system. The OAuth2 client secrets were stored in a recoverable way, so that an attacker that got access to a backup of the database and the Nextcloud config file, would be able to decrypt them. It is recommended
- 7.8 High severity
security-advisories: Improper Control of Generation of Code
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with your computer. A code injection in Nextcloud Desktop Client for macOS allowed to load arbitrary code when starting the client with DYLD_INSERT_LIBRARIES set in the enviromen
- 8.1 High severity
security-advisories: Improper Preservation of Permissions
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 Nextcl
- 7.5 High severity
security-advisories: Improper Authentication
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
- 9.8 Critical severity
nextcloudpi: Improper Neutralization of Special Elements used in an OS Command
NextcloudPi is a ready to use image for Virtual Machines, Raspberry Pi, Odroid HC1, Rock64 and other boards. A command injection vulnerability in NextCloudPi allows command execution as the root user via the NextCloudPi web-panel. Due to a security misconfigur
- 9.8 Critical severity
security-advisories: Missing Authentication for Critical Functionality
Nextcloud Global Site Selector is a tool which allows you to run multiple small Nextcloud instances and redirect users to the right server. A problem in the password verification method allows an attacker to authenticate as another user. It is recommended that
- 9.8 Critical severity
security-advisories: Improper Restriction of Excessive Authentication Attempts
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 a
- 9.8 Critical severity
security-advisories: Server-Side Request Forgery
Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Starting in version 1.13.0 and prior to version 2.2.8 and 3.3.0, an attacker can use an unprotected endpoint in the Mail app to perform a SSRF attack. Nextcloud Mail app version
- 9.8 Critical severity
security-advisories: Server-Side Request Forgery
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, 2
- 7.1 High severity
security-advisories: Improper Access Control
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
- 8.8 High severity
security-advisories: Cleartext Storage of Sensitive Information
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 user
- 7.5 High severity
security-advisories: Improper Restriction of Excessive Authentication Attempts
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.
- 7.8 High severity
security-advisories: Improper Access Control
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 a
- 7.7 High severity
security-advisories: Improper Access Control
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
- 7.8 High severity
security-advisories: Improper Limitation of a Pathname to a Restricted Directory
Nextcloud Talk Android allows users to place video and audio calls through Nextcloud on Android. Prior to version 17.0.0, an unprotected intend allowed malicious third party apps to trick the Talk Android app into writing files outside of its intended cache di
- 8.1 High severity
security-advisories: Missing Encryption of Sensitive Data
user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Starting in version 1.0.0 and prior to version 1.3.3, an attacker that obtained at least read access to a snapshot of the database can impersonate the Nextcloud serv
- 8.8 High severity
security-advisories: Improper Handling of Insufficient Privileges
Nextcloud Server is a space for data storage on Nextcloud, a self-hosted productivity playform. In NextCloud Server versions 25.0.0 until 25.0.7 and 26.0.0 until 26.0.2 and Nextcloud Enterprise Server versions 19.0.0 until 19.0.13.9, 20.0.0 until 20.0.14.14, 2
- 8.1 High severity
security-advisories: Improper Access Control
NextCloud Server and NextCloud Enterprise Server provide file storage for Nextcloud, a self-hosted productivity platform. In NextCloud Server versions 25.0.0 until 25.0.7 and 26.0.0 until 26.0.2 and Nextcloud Enterprise Server versions 21.0.0 until 21.0.9.12,
- 9.1 Critical severity
security-advisories: Improper Restriction of Excessive Authentication Attempts
NextCloud Server and NextCloud Enterprise Server provide file storage for Nextcloud, a self-hosted productivity platform. In NextCloud Server versions 25.0.0 until 25.0.7 and 26.0.0 until 26.0.2 and Nextcloud Enterprise Server versions 21.0.0 until 21.0.9.12,
- 7.5 High severity
security-advisories: Improper Restriction of Excessive Authentication Attempts
Nextcloud Server is a data storage system for Nextcloud, a self-hosted productivity platform. When multiple requests are sent in parallel, all of them were executed even if the amount of faulty requests succeeded the limit by the time the response was sent to
- 8.8 High severity
cookbook: Improper Neutralization of Special Elements used in an OS Command
NextCloud Cookbook is a recipe library app. Prior to commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch, the `pull-checks.yml` workflow is vulnerable to command injection attacks because of using an untrusted `github.head_ref
- 9.8 Critical severity
security-advisories: Improper Restriction of Excessive Authentication Attempts
user_oidc app is an OpenID Connect user backend for Nextcloud. Authentication can be broken/bypassed in user_oidc app. It is recommended that the Nextcloud user_oidc app is upgraded to 1.3.2
- 7.5 High severity
security-advisories: Improper Restriction of Excessive Authentication Attempts
Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. In Nextcloud Server 24.0.0 prior to 24.0.11 and 25.0.0 prior to 25.0.5; as well as Nextcloud Server Enterprise 23.0.0 prior to 23.0.12.6, 24.0.0 prior to 24.0.11,
- 8.8 High severity
security-advisories: Improper Access Control
Nextcloud is a personal home server system. Depending on the set up tags and other workflows this issue can be used to limit access of others or being able to grant them access when there are system tag based files access control or files retention rules. It i
- 7.5 High severity
security-advisories: Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
Nextcloud server is an open source home cloud implementation. In affected versions the generated fallback password when creating a share was using a weak complexity random number generator, so when the sharer did not change it the password could be guessable t
- 8.8 High severity
security-advisories: Unrestricted Upload of File with Dangerous Type
Nextcloud server is an open source home cloud implementation. In affected versions admins of a server were able to upload a logo or a favicon and to provided a file name which was not restricted and could overwrite files in the appdata directory. Administrator
- 7.5 High severity
security-advisories: Uncontrolled Resource Consumption
Nextcloud server is an open source home cloud implementation. In releases of the 25.0.x branch before 25.0.3 an inefficient fetch operation may impact server performances and/or can lead to a denial of service. This issue has been addressed and it is recommend
- 8.8 High severity
security-advisories: Use of Incorrectly-Resolved Name or Reference
Nextcloud server is an open source home cloud implementation. In affected versions when a recipient receives 2 shares with the same name, while a memory cache is configured, the second share will replace the first one instead of being renamed to `{name} (2)`.
- 8.8 High severity
security-advisories: Improper Neutralization of Special Elements used in an OS Command
Nextcloud server is an open source home cloud implementation. In affected versions a missing scope validation allowed users to create workflows which are designed to be only available for administrators. Some workflows are designed to be RCE by invoking define
- 8.1 High severity
security-advisories: Incorrect Permission Assignment for Critical Resource
Nextcloud server is an open source, personal cloud implementation. In versions from 24.0.0 and before 24.0.9 a user could escalate their permissions to delete files they were not supposed to deletable but only viewed or downloaded. This issue has been addresse