Detections
Analytics
RHEL-09-213070 - RHEL 9 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution.
Information
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 be either hardware-enforced or software-enforced with hardware providing the greater strength of mechanism.Examples of attacks are buffer overflow attacks.
The sysctl --system command will load settings from all system configuration files. All configuration files are sorted by their filename in lexicographical order, regardless of the directories in which they reside. If multiple files specify the same option, the entry in the file with the lexicographically latest name will take precedence. Files are read from directories in the following list from top to bottom. Once a file of a given filename is loaded, any file of the same name in subsequent directories is ignored.
/etc/sysctl.d/*.conf
/run/sysctl.d/*.conf
/usr/local/lib/sysctl.d/*.conf
/usr/lib/sysctl.d/*.conf
/lib/sysctl.d/*.conf
/etc/sysctl.conf
Satisfies: SRG-OS-000433-GPOS-00193, SRG-OS-000480-GPOS-00227
Solution
Configure RHEL 9 to implement ASLR.$ echo 'kernel.randomize_va_space = 2' | sudo tee /etc/sysctl.d/99-kernel_randomize_va_space.conf
Remove any configurations that conflict with the above from the following locations:
/run/sysctl.d/*.conf
/usr/local/lib/sysctl.d/*.conf
/usr/lib/sysctl.d/*.conf
/lib/sysctl.d/*.conf
/etc/sysctl.conf
/etc/sysctl.d/*.conf
Issue the following command to make the changes take effect:
$ sudo sysctl --system
See Also
https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_RHEL_9_V2R9_STIG.zip
Item Details
Audit Name: DISA Red Hat Enterprise Linux 9 STIG v2r9
Category: SYSTEM AND INFORMATION INTEGRITY
References: 800-53|SI-16, CAT|II, CCI|CCI-002824, Rule-ID|SV-257809r1208769_rule, STIG-ID|RHEL-09-213070, Vuln-ID|V-257809
Plugin: Unix
Control ID: 1dbcf26089bafd3aa6432d519547ab2b5754321262feaf9abb6bae8f4d533840