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cis-ubuntu1204-v110-2-16

DevOps & Security
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Add noexec Option to /run/shm Partition

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_12.04_LTS_Server_Benchmark_v1.1.0/cis-ubuntu1204-v110-2-16/SKILL.md

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2.16 Add noexec Option to /run/shm Partition (Scored)

Profile Applicability

  • Level 1

Description

Set noexec on the shared memory partition to prevent programs from executing from there.

Rationale

Setting this option on a file system prevents users from executing programs from shared memory. This deters users from introducing potentially malicious software on the system.

Audit Procedure

Using Command Line

grep /run/shm /etc/fstab | grep noexec
mount | grep /run/shm | grep noexec

Expected Result

Both commands should return output showing noexec is set. If either command emits no output then the system is not configured as recommended.

Remediation

Using Command Line

Edit the /etc/fstab file and add noexec to the fourth field (mounting options). Look for entries that have mount points that contain /run/shm. See the fstab(5) manual page for more information.

mount -o remount,noexec /run/shm

Default Value

By default, the noexec option is not set on the /run/shm partition.

References

  • CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0

Profile

Level 1 - Scored