OpenControls Logo

STIG Viewer

STIGViewer Support

AlmaLinux OS 9 must clear memory when it is freed to prevent use-after-free attacks.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-269451ALMA-09-044790SV-269451r1069342_ruleCCI-002824medium
Description
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. Poisoning writes an arbitrary value to freed pages, so any modification or reference to that page after being freed or before being initialized will be detected and prevented. This prevents many types of use-after-free vulnerabilities at little performance cost. Also prevents leak of data and detection of corrupted memory. init_on_free is a Linux kernel boot parameter that enhances security by initializing memory regions when they are freed, preventing data leakage. This process ensures that stale data in freed memory cannot be accessed by malicious programs. SLUB canaries add a randomized value (canary) at the end of SLUB-allocated objects to detect memory corruption caused by buffer overflows or underflows. Redzoning adds padding (red zones) around SLUB-allocated objects to detect overflows or underflows by triggering a fault when adjacent memory is accessed. SLUB canaries are often more efficient and provide stronger detection against buffer overflows compared to redzoning. SLUB canaries are supported in hardened Linux kernels like the ones provided by Linux-hardened. SLAB objects are blocks of physically contiguous memory. SLUB is the unqueued SLAB allocator. Satisfies: SRG-OS-000433-GPOS-00192, SRG-OS-000134-GPOS-00068
STIGDate
Cloud Linux AlmaLinux OS 9 Security Technical Implementation Guide2026-02-27

Related Frameworks

1 mapping across 4 frameworks
SCF0 mappings

No source states a mapping between these directly.

Also reachable in 3 hops (5) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

CFG-02Secure Baseline Configurations
1.00
CRY-01Use of Cryptographic Controls
1.00
DCH-01Data Protection
1.00
IAC-21Least Privilege
1.00
SEA-10Memory Protection
1.00
NIST 800-530 mappings

No source states a mapping between these directly.

Also reachable in 2 hops (14) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

AC-6(10)Prohibit Non-privileged Users from Executing Privileged Functions
1.00
AU-12Audit Record Generation
1.00
AU-3(1)Additional Audit Information
1.00
CM-6Configuration Settings
1.00
CM-7Least Functionality
1.00
CM-7(2)Prevent Program Execution
1.00
SC-2Separation of System and User Functionality
1.00
SC-3Security Function Isolation
1.00
SC-39Process Isolation
1.00
SC-5Denial-of-service Protection
1.00

+4 more (top 10 by confidence shown)

CCI1 mapping
CCI-002824
1.00
NIST CSF 2.00 mappings

No source states a mapping between these directly.

Also reachable in 3 hops (1) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

PR.DS-10
1.00

Who does this work

7 NICE work roles and 7 EC-Council certifications.

This is an inference across published mappings, not a single claim by anyone. This check maps to a control, which maps to a Cybersecurity Framework outcome, which NIST assigns to the work roles below. EC-Council separately maps its certifications to those same roles.

A certification prepares someone for a role. It is not evidence that a holder is qualified, and neither NIST nor EC-Council has stated that any certification here addresses this check.

Work-role assignments published by NIST (NICE Framework Components 2.2.0 and the CSF 2.0 OLIR crosswalk). Certification mappings published by EC-Council.

Details

Check Text (C-269451r1069342_chk)

Verify that GRUB2 is configured to mitigate use-after-free vulnerabilities by employing memory poisoning. Inspect the "GRUB_CMDLINE_LINUX" entry of /etc/default/grub as follows: $ sudo grep -i grub_cmdline_linux /etc/default/grub GRUB_CMDLINE_LINUX="... init_on_free=1" If "init_on_free=1"is missing or commented out, this is a finding.

Fix Text (F-73383r1069121_fix)

Configure AlmaLinux OS 9 to enable init_on_free with the following command: $ sudo grubby --update-kernel=ALL --args="init_on_free=1" Regenerate the GRUB configuration: $ sudo grub2-mkconfig -o /boot/grub2/grub.cfg Reboot the system: $ sudo reboot