Insertion of Sensitive Information into Log File
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.
CWE-532 - Insertion of Sensitive Information into Log File
It's quite common for applications to save logs. For example, whenever a user requests a resource from a particular website, the web server writes information about the request to a log file. These files are helpful for identifying abnormal system activity, bugs, and evaluating the security controls of the application. Security of log files is critical for the overall security of the application and its confidential resources. An application that lacks appropriate logging levels can expose sensitive user data and system information stored on the log files to malicious users. This info can be exploited to compromise your system.