Title

The Ubuntu operating system 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 non-executable 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 the Ubuntu operating system implements address space layout randomization (ASLR). Check that ASLR is configured on the system with the following command: # sudo sysctl kernel.randomize_va_space kernel.randomize_va_space = 2 If nothing is returned; we must verify the kernel parameter "randomize_va_space" is set to "2" with the following command: # kernel.randomize_va_space" /etc/sysctl.conf /etc/sysctl.d/* kernel.randomize_va_space = 2 If "kernel.randomize_va_space" is not set to "2", this is a finding.

Fix Text

Configure the operating system implement virtual address space randomization. Set the system to the required kernel parameter by adding the following line to "/etc/sysctl.conf" (or modify the line to have the required value): kernel.randomize_va_space=2

Additional Identifiers

Rule ID: SV-90501r2_rule

Vulnerability ID: V-75821

Group Title:

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