The objective of PMC10 is to define a set of Alerts and Reports that will allow confidence in the integrity of the auditing system, such that the output of this system can be relied upon in a court of law.
Protective Monitoring, also known as Good Practice Guide 13,or GPG13, is a UK government recommended set of people and business processes and technology to improve company risk profiles.
The GPG13 standard includes twelve Protective Monitoring Controls,. The below section explains what requirements must be met to meet your obligations for Protective Monitoring Control number ten.
Depending on the Impact Level of the organisations data that you are trying to protect you will have one of four recording profiles.
The required Recording Profiles for each Impact Level Data is described below:
Impact Level 1 Data – Recording Profile Aware
Impact Level 2 Data – Recording Profile Deter
Impact Level 3 Data – Recording Profile Deter
Impact Level 4 Data – Recording Profile Detect and Resist
Impact Level 5 Data – Recording Profile Defend
Impact Level 6 Data – Recording Profile Defend
Below is a summary of your obligations under each recording profile:
Aware
Report and Alert on Log Cleared or Reset, Log collection errors, and threshold exceptions
Report on status of active log storage, space allocated, space used, space remaining and total record count
Deter
Ensure you meet the requirements of lower recording profiles
Report on status of active log storage, space allocated, space used, space remaining and total record count trended in a graph over time
Report on status of active log storage, space allocated, space used, space remaining and total record count, plus log rotation information
Your SIEM solution should be able to prove chain of custody, including each part of the chain adds source and origin information. Original timestamps should not be modified
Report on log sources
Your SIEM solution should be able to prove chain of custody, including each part of the chain adds source and origin information, trended in a graphical format over time
Detect and Resist
Ensure you meet the requirements of lower recording profiles
Report and Alert on integrity checking failures anywhere within the chain of custody
Report on log access requests via queries or reports
The SIEM should have the capability to search online and archived log data
Defend
Ensure you meet the requirements of lower recording profiles
Technology Required
Log Management Software
The Log Management Software should be able to digitally sign the logs. At the higher marked data levels it would also be recommended to support encryption and or a hashing function.
Important to ensure that the Log Management layer does NOT rely on Relational Databases, unless you are collecting logs from a very limited number of devices, as these types of systems will not scale in the majority of environments.
While Appliance based solutions have the advantage of being quick to install, they require specialist knowledge to maintain and support. Often it would be better to obtain software that will run on your current server technology, that can be easily scaled and more importantly, easily supported within the existing support structure.
Security Event Management Software
You need to be able to alert on a number of different criteria. Typically this would require a SEM that has the ability to Alert when a number of different criteria is met, rather than basic Alerts. One of the risks of the SEM solution is that you are overloaded with Alerts, that are not relevant, and hence ignored by the Security response team.
As an example, if an Admin user were to login out side of business hours, create a new user and add that user to a privilege group, it would be much more preferable to receive a single High Priority Alert, rather than a number of individual Alerts. This allows you to filter the number of Alerts created to a manageable number.
A second recommendation would be that your SEM software is able to automatically responded to Alerts by running scripts. This would allow you to automate responses for common tasks, for example if you get an Alert about a Virus that was blocked at the boundary , the typical response would be to ensure the boundary device has the latest Virus Signature. Rather than manually checking this every time a Virus is detected you could automatically script this response. The alternative us manual updates, which becomes a burden on the support staff.
Notes:
This Protective Monitoring Control defines the Reporting and Alerting Framework capabilities that are required to meet your obligation under the good practice guide. Ensure you SIEM has all of the capabilities listed.