ownCloud Server before 8.1.11, 8.2.x before 8.2.9, 9.0.x before 9.0.7, and 9.1.x before 9.1.3 allows remote authenticated users to cause a denial of service (server hang and logfile flooding) via a one bit BMP file.

The autocomplete feature in the E-Mail share dialog in ownCloud Server before 8.1.11, 8.2.x before 8.2.9, 9.0.x before 9.0.7, and 9.1.x before 9.1.3 allows remote authenticated users to obtain sensitive information via unspecified vectors.

The password reset functionality in ownCloud Server before 8.1.11, 8.2.x before 8.2.9, 9.0.x before 9.0.7, and 9.1.x before 9.1.3 sends different error messages depending on whether the username is valid, which allows remote attackers to enumerate user names via a large number of password reset attempts.