1.24 RHEL-09-213025

Information

RHEL 9 must restrict exposed kernel pointer addresses access.

GROUP ID: V-257800
RULE ID: SV-257800r1044851

Exposing kernel pointers (through procfs or "seq_printf()") exposes kernel writeable structures, which may contain functions pointers. If a write vulnerability occurs in the kernel, allowing write access to any of this structure, the kernel can be compromised. This option disallows any program without the CAP_SYSLOG capability to get the addresses of kernel pointers by replacing them with "0".

Satisfies: SRG-OS-000132-GPOS-00067, SRG-OS-000433-GPOS-00192, SRG-OS-000480-GPOS-00227

Solution

Add or edit the following line in a system configuration file in the "/etc/sysctl.d/" directory:

kernel.kptr_restrict = 1

Reload settings from all system configuration files with the following command:

$ sudo sysctl --system

See Also

https://workbench.cisecurity.org/benchmarks/22008

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION, SYSTEM AND INFORMATION INTEGRITY

References: 800-53|SC-2, 800-53|SI-16, CAT|II, CCI|CCI-001082, CCI|CCI-002824, Rule-ID|SV-257800r1044851_rule, STIG-ID|RHEL-09-213025, Vuln-ID|V-257800

Plugin: Unix

Control ID: c87cafa83bf94038d560095ec65219bcb89419659320958be2e756541891818b