Rule ID
SV-270831r1261485_rule
Version
V1R7
CCIs
Protecting the integrity of the tools used for auditing purposes is a critical step toward ensuring the integrity of audit information. Audit information includes all information (e.g., audit records, audit settings, and audit reports) needed to successfully audit information system activity. Audit tools include, but are not limited to, vendor-provided and open source audit tools needed to successfully view and manipulate audit information system activity and records. Audit tools include custom queries and report generators. It is not uncommon for attackers to replace the audit tools or inject code into the existing tools with the purpose of providing the capability to hide or erase system activity from the audit logs. To address this risk, audit tools must be cryptographically signed to provide the capability to identify when the audit tools have been modified, manipulated, or replaced. An example is a checksum hash of the file or files.
Verify that the Advanced Intrusion Detection Environment (AIDE) is configured to use cryptographic mechanisms to protect the integrity of the audit tools.
First, verify that the audit tools are configured within AIDE's sub-configuration directory with the following command:
$ find /etc/aide/aide.conf /etc/aide/aide.conf.d/ -type f -exec grep -H -E '^(|/usr)/sbin/au(dit(ctl|d)|search|report|rules|trace)[[:space:]]' {} +
If any of the six core audit tools (for both /usr/sbin/ and /sbin/ paths) do not return from the command, or if they are not configured with the exact rule p+i+n+u+g+s+b+acl+xattrs+sha512, this is a finding.
/etc/aide/aide.conf.d/90-stig_audit_tools:/usr/sbin/auditctl p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/usr/sbin/auditd p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/usr/sbin/ausearch p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/usr/sbin/aureport p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/usr/sbin/autrace p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/sbin/auditctl p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/sbin/auditd p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/sbin/ausearch p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/sbin/aureport p+i+n+u+g+s+b+acl+xattrs+sha512
/etc/aide/aide.conf.d/90-stig_audit_tools:/sbin/autrace p+i+n+u+g+s+b+acl+xattrs+sha512Configure AIDE to protect the integrity of the audit tools by performing the following steps: Create a dedicated configuration file inside AIDE's sub-configuration directory: $ sudo nano /etc/aide/aide.conf.d/90-stig_audit_tools Add configuration rules: # Modern Canonical Paths /usr/sbin/auditctl p+i+n+u+g+s+b+acl+xattrs+sha512 /usr/sbin/auditd p+i+n+u+g+s+b+acl+xattrs+sha512 /usr/sbin/ausearch p+i+n+u+g+s+b+acl+xattrs+sha512 /usr/sbin/aureport p+i+n+u+g+s+b+acl+xattrs+sha512 /usr/sbin/autrace p+i+n+u+g+s+b+acl+xattrs+sha512 /usr/sbin/augenrules p+i+n+u+g+s+b+acl+xattrs+sha512 # Legacy Paths /sbin/auditctl p+i+n+u+g+s+b+acl+xattrs+sha512 /sbin/auditd p+i+n+u+g+s+b+acl+xattrs+sha512 /sbin/ausearch p+i+n+u+g+s+b+acl+xattrs+sha512 /sbin/aureport p+i+n+u+g+s+b+acl+xattrs+sha512 /sbin/autrace p+i+n+u+g+s+b+acl+xattrs+sha512 /sbin/augenrules p+i+n+u+g+s+b+acl+xattrs+sha512 If the legacy "/sbin/" paths are defined inside the main "/etc/aide/aide.conf" file, edit "/etc/aide/aide.conf" and comment those lines out using a "#" to prevent duplicate definition conflicts. Validate the modified AIDE configuration to ensure no syntax warnings or errors are present: $ sudo aide -c /etc/aide/aide.conf --config-check This command should return no output. Initialize the updated baseline database (this may take a few minutes): $ sudo aideinit Copy the newly generated database into the production directory: $ sudo cp -p /var/lib/aide/aide.db.new /var/lib/aide/aide.db