The IBM z/VM SYSTEM CONFIG file must be configured to clear TDISK on IPL.

From IBM z/VM Using CA VM:Secure Security Technical Implementation Guide

Associated with: CCI-001090

SV-93601r1_rule The IBM z/VM SYSTEM CONFIG file must be configured to clear TDISK on IPL.

Vulnerability discussion

Preventing unauthorized information transfers mitigates the risk of information, including encrypted representations of information, produced by the actions of prior users/roles (or the actions of processes acting on behalf of prior users/roles) from being available to any current users/roles (or current processes) that obtain access to shared system resources (e.g., registers, main memory, hard disks) after those resources have been released back to information systems. The control of information in shared resources is also commonly referred to as object reuse and residual information protection.This requirement generally applies to the design of an information technology product, but it can also apply to the configuration of particular information system components that are, or use, such products. This can be verified by acceptance/validation processes in DoD or other government agencies.There may be shared resources with configurable protections (e.g., files in storage) that may be assessed on specific information system components.

Check content

Examine the SYSTEM CONFIG file. If the “Feature” statement specifies ENABLE CLEAR_TDISK, this is not a finding.

Fix text

Ensure that the following statement is in the SYSTEM CONFIG file: FEATURES ENABLE CLEAR_TDISK Further, before a minidisk is assigned to a user, the minidisk must be formatted to clear it of any residual data. CMS FORMAT, ICKDSF, or any other low-level formatting program that erases all of the data on the minidisk may be used.

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.