Title

The web server must have Multipurpose Internet Mail Extensions (MIME) that invoke OS shell programs disabled. (Cat II impact)

Discussion

Controlling what a user of a hosted application can access is part of the security posture of the web server. Any time a user can access more functionality than is needed for the operation of the hosted application poses a security issue. A user with too much access can view information that is not needed for the user's job role, or the user could use the function in an unintentional manner. A MIME tells the web server what type of program various file types and extensions are and what external utilities or programs are needed to execute the file type. A shell is a program that serves as the basic interface between the user and the operating system, so hosted application users must not have access to these programs. Shell programs may execute shell escapes and can then perform unauthorized activities that could damage the security posture of the web server.

Check Content

Review the web server documentation and deployment configuration to determine if the OS shell is accessible by any MIME types that are enabled. If a user of the web server can invoke OS shell programs, this is a finding.

Fix Text

Configure the web server to disable all MIME types that invoke OS shell programs.

Additional Identifiers

Rule ID: SV-206380r960963_rule

Vulnerability ID: V-206380

Group Title: SRG-APP-000141

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.