Monitoring up the Stack: Identity Monitoring
As we continue up the Monitoring stack, we get to Identity Monitoring, which is a distinct set of concerns from User Activity Monitoring (the subject of the next post). In Monitoring Identity, the SIEM/Log Management systems gain visibility into the provisioning and Identity Management processes that enterprise use to identify, store and process user accounts to prepare the user to use the system. Contrast that with User Activity Monitoring, where SIEM/Log Management systems focus on monitoring how the user interacts with the system at runtime and looks for examples of bad behavior. As an example, do you remember when you got your driver’s license? All the processes that you went through at the DMV: Getting your picture taken, verifying your address, and taking the driving tests. All of those activities are related to provisioning an account, getting credentials created; that’s Identity Management. When you are asked to provide your driver’s license, say when checking in at a hotel, or by a police officer for driving too fast; that’s User Activity Monitoring. Identity Monitoring is an important first step because we need to associate a user’s identity with network events and system usage in order to perform User Activity Monitoring. Each requires a different type of Monitoring and different type of report, today we tackle Identity Management (and no, we won’t make you wait in line like the DMV). To enable Identity Monitoring, the SIEM/Log Management project inventories the relevant Identity Management processes (such as Provisioning), data stores (such as Active Directory and LDAP) and technologies (such as Identity Management suites). The inventory should include the Identity repositories that store accounts used for access to the business’ critical assets. In the old days it was as simple as going to RACF and examining the user accounts and rules for who was allowed to access what. Nowadays, there can be many repositories that store and manage account credentials, so inventorying the critical account stores is the first step. Process The next step is to identify the Identity Management processes that govern the Identity repositories. How did the accounts get into LDAP or Active Directory? Who signs off on them? Who updates them? There are many facets to consider in the Identity management lifecycle. The basic Identity Management process includes the following steps: Provisioning: account creation and registration Propagating: synchronizing or replicating the account to the account directory or database Access: accessing the account at runtime Maintenance: changing account data End of Life: Deleting and disabling accounts The Identity Monitoring system should verify events at each process step, record the events, and write the audit log messages in a way that they can be correlated for security incident response and compliance purposes. This links the event to the account(s) that initiated and authorized the action. For example, who authorized the account that were Provisioned? What manager(s) authorized the account updates? As we saw in the recent Societe Generale case, Jerome Kerviel (the trader who lost billions of the bank’s money) was originally an IT employee who moved over to the trading desk. When he made the move from IT to trading, his account retained his IT privileges and gained new trading privileges. Snowball entitlements enabled him to both execute trades and remove logs and hide evidence. It seems likely there was a process mishap in the account update and maintenance rules that allowed this to happen, and it shows how important the identity management processes are to access control. In complex systems, the Identity Management process is often automated using an Identity Management suite. These suites generate reports for Compliance and Security purposes, these reports can be published to the SIEM/Log Management system for analysis. Whether automated with a big name suite or not, its important to start Identity Monitoring by understanding the lifecycle that governs the account data for the accounts in your critical systems. To fully close the loop, some processes also reconcile the changes with change requests (and authorizations) to ensure every change is requested and authorized. Data In addition to identifying the Identity repositories and the management processes around them, the data itself is useful to inform the auditable messages that are published to the SIEM/Log Management systems. The data aspects for collection typically include the following: User Subject (or entity) which could be a person, an organization, or a host or application. Resource Object which could be a database, a URL, component, queue or a Web Service, Attributes such as Roles, Groups and other information that is used to make authorization decisions. The identity data should be monitored to record any lifecycle events such as Create, Read, Update, Delete, and Usage events. This is important to give the SIEM/Log Management system an end to end view of the both the account lifecycle and the account data. Challenges One challenge in Identity Monitoring is that the systems that are to be monitored (such as authentication systems) sport byzantine protocols and are not easy to get data and reports out of. This may require some extra spelunking to find the optimal protocol to use to communicate with the Identity repository. The good news is this is a one-time effort during implementation. These protocols do not change frequently. Another challenge is the accuracy of associating the user identity with the activity that a SIEM collects. Simply matching user ID to IP or MAC address is limited, so heuristic and deterministic algorithms are used to help associate users with events. The association can be performed by the collector, but more commonly this feature is integrated within the SIEM engine as an log/event enrichment activity. The de-anonymization occurs as data is normalized, and stored with the events. Federated identity systems that separate the authentication, authorization and attribution create additional challenges, because the end to end view of the account in both the Identity Provider and in the Relying Party is not usually easy to attain. Granted this is the point of Federation, which resolves the relationship at runtime, but it’s worth pointing out the difficulty this presents to end to end
