Title

A file integrity baseline including cryptographic hashes must be maintained. (Cat II impact)

Discussion

A file integrity baseline is a collection of file metadata which is to evaluate the integrity of the system. A minimal baseline must contain metadata for all device files, setuid files, setgid files, system libraries, system binaries, and system configuration files. The minimal metadata must consist of the mode, owner, group owner, and modification times. For regular files, metadata must also include file size and a cryptographic hash of the file’s contents.

Check Content

Verify a system integrity baseline is maintained. The baseline has been updated to be consistent with the latest approved system configuration changes. The Advanced Intrusion Detection Environment (AIDE) is included in the distribution of SLES. Other host intrusion detection system (HIDS) software is available but must be checked manually. Procedure: # grep DB /etc/aide.conf If /etc/aide.conf does not exist AIDE has not been installed. Unless another HIDS is used on the system, this is a finding. Examine the response for "database". This indicates the location of the system integrity baseline database used as input to a comparison. # ls -la <DB> If no "database" file as defined in /etc/aide.conf exists, a system integrity baseline has not been created. This is a finding. Ask the SA when the last approved system configuration changes occurred. If the modification date of the AIDE database is prior to the last approved configuration change, this is a finding.

Fix Text

Regularly rebuild the integrity baseline, including cryptographic hashes, for the system to be consistent with the latest approved system configuration. Procedure: After an approved modification to the system configuration has been made perform: # aide -u This will update the database.

Additional Identifiers

Rule ID: SV-44764r1_rule

Vulnerability ID: V-27251

Group Title: GEN000140-3

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.