File integrity monitoring (FIM) is an IT security procedure and technology that monitors and examines operating system (OS), database, and application software files to see if they have been altered or corrupted. By contrasting the most recent versions of these files with a recognised, trusted "baseline," FIM, a type of change auditing, verifies and validates these files. If FIM discovers that files have been modified, updated, or compromised, FIM can produce warnings to ensure that more investigation and, if necessary, remediation, takes place. File integrity monitoring includes both proactive, rules-based active monitoring and reactive (forensic) audits.


Why File Integrity Monitoring?

In an IT context, FIM software will scan, examine, and report on any unforeseen modifications to crucial data. By doing this, file integrity monitoring adds a crucial layer of data, application, and file security and speeds up incident response.


1. Identifying Unlawful Activity

You need to know if a cyber attacker attempts to change any files that are essential to your operating systems or apps if they intrude into your IT environment. FIM can still identify changes to significant components of your IT environment even if log files and other detection methods are ignored or modified. You can keep an eye on and safeguard the security of your files, apps, operating systems, and data with FIM in place.


2. Identifying Unwanted Changes

File changes are frequently unintentionally made by an administrator or another employee. The effects of these modifications sometimes have minor effects that are ignored. Other times, they can lead to security backdoors, problems with business continuity, or both. By assisting you in locating the mistaken change so you can undo it or take other corrective action, file integrity monitoring makes forensics simpler.


3. Monitoring System Health and Verifying Update Status

By using the post-patch checksum to scan installed versions on various devices and locations, you may determine whether files have been updated to the most recent version.


4. Observing compliance requirements

Compliance with legal requirements like GLBA, SOX, HIPAA, and PCI DSS necessitates the capacity to audit modifications and monitor and report specific sorts of activities.


How File Integrity Monitoring Works?

FIM functions by identifying changes to files and configurations. FIM establishes a baseline when it is first installed to determine your current situation. This baseline is saved in a database as cryptographic hashes that cannot be changed after they are created and cannot be modified, destroyed, or altered.


An agent-based FIM will continuously compare data on the state of the monitored elements against the baseline. Better options, like CimTrak, operate at the OS kernel level to identify change as soon as it happens without constantly scanning files. Because of this, the CimTrak agent is incredibly lightweight and may run invisibly in the background on a system.


FIM is composed mostly of three elements:


Database: 

Cryptographic hashes representing the original state of your files and configurations are stored in this database.


Agents:

These computer hardware and software measuring devices provide data back to your database for comparison.


User Interface:

The administrative users' user interface acts as the central portal for reporting, evaluation, change monitoring, and change control.