- 필수 기능
- 시작하기
- Glossary
- 표준 속성
- Guides
- Agent
- 통합
- 개방형텔레메트리
- 개발자
- API
- Datadog Mobile App
- CoScreen
- Cloudcraft
- 앱 내
- 서비스 관리
- 인프라스트럭처
- 애플리케이션 성능
- APM
- Continuous Profiler
- 스팬 시각화
- 데이터 스트림 모니터링
- 데이터 작업 모니터링
- 디지털 경험
- 소프트웨어 제공
- 보안
- AI Observability
- 로그 관리
- 관리
To configure the system to prevent the cramfs
kernel module from being loaded, add the following line to the file /etc/modprobe.d/cramfs.conf
:
install cramfs /bin/false
This effectively prevents usage of this uncommon filesystem.
The cramfs
filesystem type is a compressed read-only
Linux filesystem embedded in small footprint systems. A
cramfs
image can be used without having to first
decompress the image.
Removing support for unneeded filesystem types reduces the local attack surface of the server.
The following script can be run on the host to remediate the issue.
#!/bin/bash
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then
if LC_ALL=C grep -q -m 1 "^install cramfs" /etc/modprobe.d/cramfs.conf ; then
sed -i 's#^install cramfs.*#install cramfs /bin/false#g' /etc/modprobe.d/cramfs.conf
else
echo -e "\n# Disable per security requirements" >> /etc/modprobe.d/cramfs.conf
echo "install cramfs /bin/false" >> /etc/modprobe.d/cramfs.conf
fi
if ! LC_ALL=C grep -q -m 1 "^blacklist cramfs$" /etc/modprobe.d/cramfs.conf ; then
echo "blacklist cramfs" >> /etc/modprobe.d/cramfs.conf
fi
else
>&2 echo 'Remediation is not applicable, nothing was done'
fi
The following playbook can be run with Ansible to remediate the issue.
- name: Ensure kernel module 'cramfs' is disabled
lineinfile:
create: true
dest: /etc/modprobe.d/cramfs.conf
regexp: install\s+cramfs
line: install cramfs /bin/false
when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
tags:
- NIST-800-171-3.4.6
- NIST-800-53-CM-6(a)
- NIST-800-53-CM-7(a)
- NIST-800-53-CM-7(b)
- disable_strategy
- kernel_module_cramfs_disabled
- low_complexity
- low_severity
- medium_disruption
- reboot_required
- name: Ensure kernel module 'cramfs' is blacklisted
lineinfile:
create: true
dest: /etc/modprobe.d/cramfs.conf
regexp: ^blacklist cramfs$
line: blacklist cramfs
when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
tags:
- NIST-800-171-3.4.6
- NIST-800-53-CM-6(a)
- NIST-800-53-CM-7(a)
- NIST-800-53-CM-7(b)
- disable_strategy
- kernel_module_cramfs_disabled
- low_complexity
- low_severity
- medium_disruption
- reboot_required