Event Log Monitoring for the PCI DSSThis article has been produced to assist anyone concerned with ensuring their organization canmeet PCI DSS obligations for event log management - "PCI DSS Section 10.2 Implementautomated audit trails for all system components..." There are typically two concerns that need to be addressed - first, "what is the best way to gather and centralize event logs?" And second, "what do we need to do with the event logs once we have them stored centrally? (And how will we cope with the volume?)"To the letter of the PCI DSS, you are obliged to make use of event and audit logs in order to trackuser activity for any device within scope i.e. all devices which either touch cardholder data orhave access to cardholder data processing systems. The full heading of the Log Tracking sectionof the PCI DSS is as follows -CLICK HERE TO GET INSTANT ACCESS TO Z CODE SYSTEMDownload this document if link is not clickable"PCI DSS Requirement 10: Track and monitor all access to network resources and cardholder data"Logging mechanisms and the ability to track user activities are critical in preventing, detecting,or minimizing the impact of a data compromise. The presence of logs in all environments allowsthorough tracking, alerting, and analysis when something does go wrong. Determining the causeof a compromise is very difficult without system activity logs.Given that many PCI DSS estates will be geographically widespread it is always a good idea touse some means of centralizing log messages, however, you are obliged to take this routeanyway if you read section 10.5.3 of the PCI DSS -"Promptly back up audit trail files to a centralized log server or media that is difficult to alter"The first obstacle to overcome is the gathering of event logs. Unix and Linux hosts can utilizetheir native syslogd capability, but Windows servers will need to use a third party Windows Sylogagent to transfer Windows Event Logs via syslog. This will ensure all event log messages form
Windows servers are backed up centrally in accordance with the PCI DSS standard. Similarly,Oracle and SQL Server based applications will also require a Syslog Agent to extract log entriesfor forwarding to the central syslog server. Similarly, IBM z/OS mainframe or AS/400 systems willalso need platform-specific agent technology to ensure event logs are backed up.Of course, Firewalls and Intrusion Protection/Detection System (IPS/IDS), as well as the majority ofswitches and routers all natively generate syslog messages.File-Integrity Monitoring and Vulnerability ScanningWhile we are on the subject of deployment of agents to platforms for event log monitoring, it isworth considering the other dimensions of the PCI DSS, namely file-integrity monitoring andvulnerability scanning/assessment.Both of these functions can be addressed using an agent on board your servers and workstations.File-Integrity monitoring (see section 11.5 of the PCI DSS) is necessary to ensure key programand operating system files are not infiltrated by Trojans or other malware, and that backdoorcode is not inserted within applications. File-Integrity Monitoring should be deployed to all PCsand Epos systems, Windows Servers, Unix and Linux hosts.Vulnerability Scanning is a further element of the PCI DSS and requires all devices to be scannedregularly for the presence of security vulnerabilities. The key benefit of an agent based approachis that vulnerability scans can be performed continuously and any configuration changesrendering your PCs/Epos/Servers less secure or less hardened will be identified and alerted toyou. The agent will need valid PCI Security Settings/Vulnerability Assessment/PCI HardeningChecklists to be applied.Event Log Backup to a Centralized ServerOnce assembled, the Audit trail history must be backed up in a way that is "difficult to alter".Traditionally, write-once media has been used to ensure event histories cannot be altered butmost centralized log server solutions now employ file-integrity monitoring as a means ofdetecting any attempt to change or edit the event log backup.So in terms of our two initial questions, we have fully covered the first, but what about the nextlogical question of What do we do with - and how do we cope with - the event logs gathered?"PCI DSS Section 10.6 Review logs for all system components at least daily"This is the part of the standard that causes most concern. If you consider the volume of eventlogs that may be generated by a typical firewall this can be significant, but if you are managing a
retail estate of 800 stores with 7,500 devices within scope of the PCI DSS, the task of reviewinglogs from devices is going to be impossible to achieve. This may be a good time to consider someautomation of the process...?The Security Information and Event Management or SIEM market as defined by Gartner coversthe advanced generation of solutions that harvest audit and event logs, and then parse orinterpret the events e.g. store events by device, event type and severity, and analyze the detailswithin event logs as they are stored. In fact, the PCI DSS recognizes the potential value of thiskind of technology"Log harvesting, parsing, and alerting tools may be used to meet compliance with Requirement10.6 of the PCI DSS"SIEM technology allows event logs to be automatically and intelligently managed such that onlygenuinely serious security events are alerted. The best SIEM technology can distinguish betweentrue hacker activity running a brute force attack and a user who has simply forgotten theirpassword and is repeatedly trying to access their account. Naturally there is an amount ofcustomization required for each environment as every organizations network, systems,applications and usage patterns are unique as are the corresponding event log volumes andtypes.The PCI Event log management process can be approached in three stages, ensuring that there isa straightforward progression through becoming compliant with the PCI DSS standard andbecoming fully in control of your PCI Estate. The tree phases will assist you in understanding howyour PCI Estate functions normally and, as a result, placing all genuine security threats into thespotlight.1. GATHER - Implement the SIEM system and gather all event logs centrally - the SIEM technologywill provide a keyword index of all events, reported by device type, event severity and even withjust the basic, pre-defined rules applied, the volumes of logs by type can be established. Youneed to get familiar with the types of event log messages being collected and what good lookslike for your estate.2. PROFILE - Refinement of event type identification and thresholds - once an initial baseliningperiod has been completed we can then customize rules and thresholds to meet the profile ofyour estate, with the aim of establishing a profiled, steady-state view of event types andvolumes. Even though all logs must be gathered and retained for the PCI DSS, there is a largeproportion of events which arent significant on a day-to-day basis and the aim is tode-emphasize these in order to promote focus on those events which are significant.
3. FOCUS - simple thresholding for event types is adequate for some significant security events,such as anti-virus alerts or IPS signature detections, but for other security events it is necessaryto correlate and pattern-match combinations and sequences of event. SIEM only becomesvaluable when it is notifying you of a manageable number of significant security events.It is important to note that even when certain events are being de-emphasized, these are stillbeing retained in line with the PCI DSS guidelines which are to retain logs for 12 months. At least3 months of event logs must be in an on-line, searchable format for at least 3 months, andarchived for 12 months.Again, the archived and on-line log repositories must be protected fromany editing or tampering so write-once media and file integrity monitoring must be used topreserve log file integrity.CLICK HERE TO GET INSTANT ACCESS TO Z CODE SYSTEMDownload this document if link is not clickableArticle source = ezinearticles.com/?Event-Log-Monitoring-for-the-PCI-DSS