Title

NixOS must implement address space layout randomization to protect its memory from unauthorized code execution. (Cat II impact)

Discussion

Some adversaries launch attacks with the intent of executing code in nonexecutable regions of memory or in memory locations that are prohibited. Security safeguards employed to protect memory include, for example, data execution prevention and address space layout randomization. Data execution prevention safeguards can either be hardware-enforced or software-enforced with hardware providing the greater strength of mechanism. Examples of attacks are buffer overflow attacks.

Check Content

Verify NixOS enables address space layout randomization with the following command: $ sudo sysctl kernel.randomize_va_space kernel.randomize_va_space = 2 If "kernel.randomize_va_space" does not have a value of "2" or is missing, this is a finding.

Fix Text

Configure /etc/nixos/configuration.nix to enable ASLR by adding the following configuration settings: boot.kernel.sysctl = { "kernel.randomize_va_space" = 2; }; Rebuild the system with the following command: $ sudo nixos-rebuild switch

Additional Identifiers

Rule ID: SV-268161r1039371_rule

Vulnerability ID: V-268161

Group Title: SRG-OS-000433-GPOS-00193

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