STIGQter: STIG Summary: Tri-Lab Operating System Stack (TOSS) 4 Security Technical Implementation Guide Version: 2 Release: 6 Benchmark Date: 01 Jul 2026:

Successful/unsuccessful uses of the openat system call in TOSS must generate an audit record.

DISA Rule

SV-253020r958446_rule

Vulnerability Number

V-253020

Group Title

SRG-OS-000064-GPOS-00033

Rule Version

TOSS-04-030670

Severity

CAT II

CCI(s)

• CCI-000172 - Generate audit records for the event types defined in AU-2 c that include the audit record content defined in AU-3.

Weight

10

Fix Recommendation

Configure the audit system to generate an audit event for any successful/unsuccessful use of the "openat" command by adding or updating the following rules in the "/etc/audit/rules.d/audit.rules" file:

-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -k perm_access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -k perm_access

-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -k perm_access
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -k perm_access

The audit daemon must be restarted for the changes to take effect.

Check Contents

Verify TOSS generates an audit record when successful/unsuccessful attempts to use the "openat" system calls by performing the following command to check the file system rules in "/etc/audit/audit.rules":

$ sudo grep -iw openat /etc/audit/audit.rules

-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -k perm_access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -k perm_access

-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -k perm_access
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -k perm_access

If the command does not return all lines, or the lines are commented out, this is a finding.

Vulnerability Number

V-253020

Documentable

False

Rule Version

TOSS-04-030670

Severity Override Guidance

Verify TOSS generates an audit record when successful/unsuccessful attempts to use the "openat" system calls by performing the following command to check the file system rules in "/etc/audit/audit.rules":

$ sudo grep -iw openat /etc/audit/audit.rules

-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -k perm_access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -k perm_access

-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -k perm_access
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -k perm_access

If the command does not return all lines, or the lines are commented out, this is a finding.

Check Content Reference

M

Target Key

5469