Ensure noexec option set on /dev/shm partition
Profile
Level 1 - Server, Level 1 - Workstation, Assessment: Automated
Description
The noexec mount option specifies that the filesystem cannot contain executable binaries.
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
Command Line
- IF - a separate partition exists for
/dev/shm, verify that the noexec option is set.
Nothing should be returned
Expected Result
Nothing should be returned
Remediation
Command Line
- IF - a separate partition exists for
/dev/shm.
Edit the /etc/fstab file and add noexec to the fourth field (mounting options) for the /dev/shm partition. See the fstab(5) manual page for more information.
Example:
tmpfs /dev/shm tmpfs defaults,rw,nosuid,nodev,noexec,relatime 0 0
Run the following command to remount /dev/shm with the configured options:
Note: It is recommended to use tmpfs as the device/filesystem type as /dev/shm is used as shared memory space by applications.
Default Value
Not configured by default.
References
- See the fstab(5) manual page for more information.
- NIST SP 800-53 Rev. 5: AC-3, MP-2
- NIST SP 800-53 Revision 5 :: CM-7 (2)
- RHEL 8 STIG Vul ID: V-230510
- RHEL 8 STIG Rule ID: SV-230510r854051
CIS Controls
v8 - 3.3 Configure Data Access Control Lists (IG 1, IG 2, IG 3)
v7 - 14.6 Protect Information through Access Control Lists (IG 1, IG 2, IG 3)
MITRE ATT&CK Mappings: T1204, T1204.002 | TA0005 | M1022