Webmin CGI Command Injection Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Webmin. Authentication is required to exploit this vulnerability. The specific flaw exists within the handling of CGI requests. The issue results from the lack of proper validation of a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-22346.
Usermin 0.980 through 1.x before 1.660 allows uconfig_save.cgi sig_file_free remote code execution because it uses the two argument (not three argument) form of Perl open.
Usermin through 1.850 allows a remote authenticated user to execute OS commands via command injection in a filename for the GPG module.
Improper Access Control to Remote Code Execution in GitHub repository webmin/webmin prior to 1.990.
rpc.cgi in Webmin through 1.920 allows authenticated Remote Code Execution via a crafted object name because unserialise_variable makes an eval call. NOTE: the Webmin_Servers_Index documentation states "RPC can be used to run any command or modify any file on a server, which is why access to it must not be granted to un-trusted Webmin users."
Arbitrary command execution can occur in Webmin through 1.962. Any user authorized for the Package Updates module can execute arbitrary commands with root privileges via vectors involving %0A and %0C. NOTE: this issue exists because of an incomplete fix for CVE-2019-12840.