An issue was discovered in the changePassword method in file /usr/share/php/openmediavault/system/user.inc in OpenMediaVault 7.4.17 allowing local authenticated attackers to escalate privileges to root.
openmediavault before 4.1.36 and 5.x before 5.5.12 allows authenticated PHP code injection attacks, via the sortfield POST parameter of rpc.php, because json_encode_safe is not used in config/databasebackend.inc. Successful exploitation allows arbitrary command execution on the underlying operating system as root.