An issue was discovered in ownCloud owncloud/core before 10.13.1. An attacker can access, modify, or delete any file without authentication if the username of a victim is known, and the victim has no signing-key configured. This occurs because pre-signed URLs can be accepted even when no signing-key is configured for the owner of the files. The earliest affected version is 10.6.0.

The Docker image of ownCloud Server through 10.11 contains a misconfiguration that renders the trusted_domains config useless. This could be abused to spoof the URL in password-reset e-mail messages.

ownCloud owncloud/core before 10.10.0 Improperly Removes Sensitive Information Before Storage or Transfer.

Session fixation on password protected public links in the ownCloud Server before 10.8.0 allows an attacker to bypass the password protection when they can force a target client to use a controlled cookie.

A receiver of a federated share with access to the database with ownCloud version before 10.8 could update the permissions and therefore elevate their own permissions.

The shareinfo controller in the ownCloud Server before 10.8.0 allows an attacker to bypass the permission checks for upload only shares and list metadata about the share.

The public share controller in the ownCloud server before version 10.8.0 allows a remote attacker to see the internal path and the username of a public share by including invalid characters in the URL.

ownCloud Server before 10.3.0 allows an attacker, who has received non-administrative access to a group share, to remove everyone else's access to that share.

An issue was discovered in ownCloud before 10.4. An attacker can bypass authentication on a password-protected image by displaying its preview.

An issue was discovered in ownCloud before 10.4. Because of an SSRF issue (via the apps/files_sharing/external remote parameter), an authenticated attacker can interact with local services blindly (aka Blind SSRF) or conduct a Denial Of Service attack.

Deleting users with certain names caused system files to be deleted. Risk is higher for systems which allow users to register themselves and have the data directory in the web root. This affects ownCloud/core versions < 10.6.

The CSRF (Cross Site Request Forgery) token check was improperly implemented on cookie authenticated requests against some ocs API endpoints. This affects ownCloud/core version < 10.6.

ownCloud (Core) before 10.5 allows XSS in login page 'forgot password.'