V-279427

Discussion

If log data is compromised, then competent forensic analysis and discovery of the true source of potentially malicious system activity is difficult, if not impossible, to achieve. In addition, access to log records provides information an attacker could potentially use to their advantage. Application servers contain admin interfaces that allow reading and manipulation of log records. Therefore, these interfaces should not allow unfettered access to those records. Application servers also write log data to log files which are stored on the OS, so appropriate file permissions must also be used to restrict access. Log information includes all information (e.g., log records, log settings, transaction logs, and log reports) needed to successfully log information system activity. Application servers must protect log information from unauthorized read access. Satisfies: SRG-APP-000118-AS-000078, SRG-APP-000119-AS-000079, SRG-APP-000120-AS-000080

Check Content

Confirm the Nutanix VM application server log files are protected from unauthorized read access.

The Nutanix AOS log files are owned by the Nutanix user and have a file permission of "640".

1. Identify the actual file name by looking at alert_manager.INFO, which is a symlink for the actual rotating file name.

$ sudo ls -al /home/nutanix/data/logs/alert_manager.INFO 
lrwxrwxrwx. 1 nutanix nutanix 75 Nov  1 17:50 /home/nutanix/data/logs/alert_manager.INFO -> alert_manager.ntnx-<CVM_NAME>.nutanix.log.INFO.<LOG_NUMBER>

2. Execute a stat command on the actual application server log file name.

$ sudo stat -c "%a %n" /home/nutanix/data/logs/alert_manager.ntnx-<CVM_NAME>.nutanix.log.INFO.<LOG_NUMBER>
640  /home/nutanix/data/logs/alert_manager.ntnx<CVM_NAME>.nutanix.log.INFO.<LOG_NUMBER>

If the output of the actual log file name is not 640, this is a finding.