BaselineWatch
Desk

UBTU-24-600150 Ubuntu 24.04 LTS must set a sticky bit on all public directories to prevent unauthorized and unintended information transferred via shared system resources.

DISA STIG library V1R7
All changes in this version
first version loaded CAT II

Maps to SC-4 via CCI-001090

Title

Ubuntu 24.04 LTS must set a sticky bit on all public directories to prevent unauthorized and unintended information transferred via shared system resources.

Control

Verify all public (world-writeable) directories have the public sticky bit set with the following command: $ sudo find / -type d -perm -002 ! -perm -1000 If any world-writable directories are found missing the sticky bit, this is a finding.

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 DoW 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.

Related controls

CCI-001090

Fix

Configure all public directories to have the sticky bit set to prevent unauthorized and unintended information transferred via shared system resources. Set the sticky bit on all public directories using the following command, replacing "[Public Directory]" with any directory path missing the sticky bit: $ sudo chmod +t [Public Directory]