Detections
Analytics

1.176 AZLX-23-002535

Information

Amazon Linux 2023 must enable discretionary access control on hardlinks.

GROUP ID: V-274169RULE ID: SV-274169r1120495

By enabling the fs.protected_hardlinks kernel parameter, users can no longer create soft or hard links to files they do not own. Disallowing such hardlinks mitigates vulnerabilities based on insecure file system accessed by privileged programs, avoiding an exploitation vector exploiting unsafe use of open() or creat().

Satisfies: SRG-OS-000312-GPOS-00123, SRG-OS-000324-GPOS-00125

Solution

Configure Amazon Linux 2023 to enable DAC on hardlinks with the following:

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

fs.protected_hardlinks = 1

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

$ sudo sysctl --system

See Also

https://workbench.cisecurity.org/benchmarks/26107

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-3(4), 800-53|AC-6(10), CAT|II, CCI|CCI-002165, CCI|CCI-002235, Rule-ID|SV-274169r1120495_rule, STIG-ID|AZLX-23-002535, Vuln-ID|V-274169

Plugin: Unix

Control ID: d08480b6913b8522d0986d70a3403a4c985c679e2307dddb8b30e46c7eee1a3e