V-275569

Discussion

Some adversaries launch attacks with the intent of executing code in nonexecutable regions of memory or in prohibited memory locations. 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 Ubuntu OS implements address space layout randomization (ASLR) by using the following command:  
  
     $ sysctl kernel.randomize_va_space 
     kernel.randomize_va_space = 2 
  
If no output is returned, verify the kernel parameter "randomize_va_space" is set to "2" by using the following command:  
  
     $ cat /proc/sys/kernel/randomize_va_space 
     2 
  
If "kernel.randomize_va_space" is not set to "2", this is a finding.  
  
Verify that a saved value of the "kernel.randomize_va_space" variable is not defined.  
  
     $ sudo grep -ER "^kernel.randomize_va_space=[^2]" /etc/sysctl.conf /etc/sysctl.d 
  
If this returns a result, this is a finding.