Tag Archives: security assessments

To be successful a SIEM implementation should follow the ISO 27001 approach

20 July 2015

Last Wednesday I participated in a workshop on Production IT Security in Frankfurt. The presentations about Security Assessments, SIEM solutions, Next Generation Firewalls and Threat Intelligence were very interesting, but, as always, I got the most valuable information from the discussions with the other attendees during coffee break. It was really amazing to hear that the attendees, although they came from different companies, talked about the same mostly negative experiences in their SIEM projects.

During my ride back to Leverkusen I had time to think about this. Expectation management was a big issue in the discussions. The PowerPoints of the vendors suggest a quick and easy installation and start-up, and with some days training in Big Data methods the SIEM operator can set up dashboards which show the current security status of your company. Far from it!

The key capabilities of a SIEM solution are:

(1) Data aggregation and correlation:  Collect event data from various sources, correlate them, and integrate them with other information sources to turn the data into useful information.

(2) Compliance: Gather compliance data to support security, governance and auditing processes.

(3) Retention and Forensic analysis: Long term storage of historical event data for correlation over time and forensic analysis in the case of a security incident.

(4) Dashboard: Turn aggregated and correlated data into informational charts to aid security staff in identifying abnormal usage patterns.

(5) Alerting: Automated analysis of correlated events and production of alerts, to notify recipients of immediate issues.

The implementation of each function requires a big effort in preparation and operation. Let me show this by the means of two examples:

(4) Dashboard. In order to find abnormal usage patterns you have to define normal usage patterns first. This takes not only time. It is really hard to find relevant patterns from the ocean of events that systems create during normal operation. To ensure fast start-up it is required to cleanup your systems of e.g. event errors created by mis-configured services before you start operation.

(5) Alerting is probably the most interesting capability of a SIEM system. It allows you to act directly upon security incidents. To get the most of alerting you have to set up an incident response process, ideally depending on the classification of the information assets to prevent wasting of time and effort.

This requires that all assets are listed in an asset repository, classified and an asset owner is assigned, before your SIEM solution goes into production.

In addition it is required that your SIEM operations group is sufficiently staffed, the operators are well-trained, and enabled to take proper actions on an incident, e.g. alerting your server operators or shutting down a server to prevent larger damage.

Sounds like the preparations required for the implementation of an Information Security Management System due to ISO 27001.

With this my advice is: For a successful and quick SIEM implementation you should follow the major steps for implementation of an ISMS.

Bonne semaine!


The Good and the Evil of Auto-Updaters

7 March 2015

This week I had a lot of delightful discussions with software developers during some security assessments.

Software development in very dynamic sectors thrives of rapid deployment of new functions and bug fixes. In particular in large IT organizations, the classic software rollout concept based on software packaging and distribution is often too slow to meet the needs of this users.

Often, developers try to solve this deployment challenge with auto-updaters. For the initial rollout classic software packaging and distribution is used. Once a bug fix or new function is regression tested a new version is build and pushed to the update server.

At every program startup the auto-updater checks the update server. If a newer program version is available the auto-updater installs them on the user’s computer and starts the new version.

This is a very charming concept. Users and developers love it, because it is fast and reliable. And help desk staff loves it because it ensures, that all users work with the same version.

Unfortunately auto-updaters are popular targets for attackers. For example, in the Home Depot data breach, which became public in November 2014, cyber criminals attacked the company’s software deployment system and deployed custom-built malware to point-of-sales devices.

It is very important that developers become aware of those attack vectors. Update servers, build servers, source control systems are very valuable targets for attackers. The mass rollout of malicious software is easy if an attacker gets access to a build or update server. And anti-malware or task virtualization software is largely useless because the attack is initiated by the end-user.

Spring is near

Spring is near

In my opinion it is very important that organizations secure their software development infrastructure and development processes, accompanied by regular security awareness trainings for developers. If possible enforce the Separation-of-Duties principle for all critical processes.

This is also true for the very popular PowerShell scripts which simplify the job of administrators. If an attacker injects some code in scripts which are used for administration of a company’s servers … Don’t panic!

That’s it for this week. Have a good weekend.