Title

The audit system must be configured to audit failed attempts to access files and programs. (Cat II impact)

Discussion

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.

Check Content

Verify auditd is configured to audit failed file access attempts. There must be an audit rule for each of the access syscalls logging all failed accesses (-F success=0) or there must both an "-F exit=-EPERM" and "-F exit=-EACCES" for each access syscall. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S openat" | grep -e "-F success=0" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S openat" | grep -e "-F exit=-EPERM" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S openat" | grep -e "-F exit=-EACCES" If an "-S openat" audit rule with "-F success" does not exist and no separate rules containing "-F exit=-EPERM" and "-F exit=-EACCES" for "openat" exist, then this is a finding.

Fix Text

Edit the audit.rules file and add the following line(s) to enable auditing of failed attempts to access files and programs: either: -a exit,always -F arch=<ARCH> -S openat -F success=0 or both: -a exit,always -F arch=<ARCH> -S openat -F exit=-EPERM -a exit,always -F arch=<ARCH> -S openat -F exit=-EACCES Restart the auditd service. # rcauditd restart OR # service auditd restart

Additional Identifiers

Rule ID: SV-45287r1_rule

Vulnerability ID: V-29237

Group Title: GEN002720-3

Expert Comments

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