Real-Time FIM for Rapid Intrusion Detection and Response - Atomicorp - Unified Security Built on OSSEC

Real-Time FIM for Rapid Intrusion Detection and Response

Employ real time file integrity monitoring (FIM) to meet always-on security requirements as well as data protection compliance standards such as PCI DSS.

Cyberattacks can be sneaky fast, executing their programs, altering your files and source code, and deleting traces of the activity. Many file integrity monitoring (FIM) programs run on a timer based model, only assessing a system daily, or even weekly, and don’t always catch these malicious changes quickly enough or they miss them all together. This can leave weeks or longer in which the malware spreads and digs in, compromising additional files and systems, stealing or ransoming financial data, and/or crippling IT and OT systems.

Against these surreptitious attacks, the real-time FIM in Atomic OSSEC detects subtle changes across your environment. With Atomic OSSEC, you capture a file instance before and after the change, analyze and benchmark against Atomicorp and crowdsourced global threat intelligence and CVE databases, and get an alert while the system isolates the malware. Atomic OSSEC empowers further response and enhanced security through rules automation and command line control so you can quarantine and remove malicious code and reverse-engineer software. Real-time FIM also collects often uncaptured artifacts for forensics, response, reporting and compliance, right down to deleted files and logs.

Watch the real-time FIM video.


The Cause for Real Time FIM

Real-time file integrity monitoring (FIM) enables you to continuously monitor an environment, detect anomalous behavior as it occurs, and reconcile changes in important files. In Atomic OSSEC, the rapid detection information captured by FIM is integrated into a response engine and toolset for blocking infected endpoints, isolating malicious files, vulnerability management, and better protecting the software supply chain against zero day. 

With this detection, you can zero in on malware, extract it, and orchestrate additional active response activities across your files, systems, and cloud and software APIs. 

The Atomic OSSEC XDR leverages checksum, SSDEEP, and fuzzy hashing in its powerful scanning. It makes comparisons against crowdsourced and Atomicorp global threat intelligence, checking for identical files, similar content, and recognizing malware without processing the whole file (e.g., fuzzy hashing). The real-time FIM detects and alerts you when malicious files are trying to access your endpoints, databases, file directories, and OS source code.

Figure: Web-based malware being uploaded to the system is captured by the FIM.

Real-time FIM

Watch the real-time FIM video.

Learn more about the Atomic OSSEC XDR.


The Cause for Real Time FIM (cont.)

What can you do with real-time FIM alerts? It’s primarily about rapid danger detection and response.

In the Atomic OSSEC system, the real-time detection spurs isolation, alerts, investigation, identification (who, what, where), and response. You’ll be able to catch subtle changes that evade timer-based FIM and determine who changed the file, when it was changed, where, and what was changed, and take rapid action. 

Real-time FIM can also be valuable for auditing and compliance, both which require regular file and system scans and the ability to capture records and artifacts for reporting.


Prevention, Detection, Response, and Recovery

Defense-in-depth security means recognizing the criticality of recovery. Detection and response are equally critical but never full-proof and you must be able to resume operations thanks to backup systems. Atomic OSSEC FIM is part of a full XDR system that can remotely back up, so even if prevention efforts aren’t enough, you still have your data, your source code, your future. 

Learn more about Atomic OSSEC FIM and watch the real-time FIM video.


FIM for PCI DSS, NIST and Other Standards and Regulations 

File integrity monitoring (FIM)—in addition to extending and deepening detection for critical enterprise IT security response and risk mitigation—is a requirement for meeting data protection standards and government regulations.

PCI DSS Requirement 11.5 specifies file integrity monitoring (FIM) as a method to alert authorized personnel against unauthorized modification of critical system or configuration files. According to PCI DSS requirements, FIM software should be configured to perform weekly critical file comparisons. That bar is very low, and doesn’t require real time FIM. However, PCI DSS v4.0, effective March 31, 2025, spells out PAN and SAD security requirements that will require PCI members to harden security over forms and other files.

PCI DSS. Credit card information is the bloodstream of business operations—a sought-after treasure by thieves and adversaries. Harden the security at the financial transaction and data handling stages as to who can be trusted with this full information, or a piece of it. Use Atomic OSSEC’s controls to scan and block access to files, including restricting access to primary account numbers (PANs) and sensitive authentication data (SADs). Atomic OSSEC provides more than 100 security rules for your PCI DSS compliance, across AIX, Linux, and Window OSs, and legacy system environments such as Linux end of life (RHEL 5, 32-bit), Windows end of life (XP, 2003, etc.), HP-UX, Solaris, Ubuntu, IoT Linux, and CentOS.

NIST. National Institute of Standards and Technology (NIST) 800-53 is a catalog of security controls to which Department of Defense contractors and subcontractors of federal agencies must adhere. The NIST 800-171 subset provides guidance specifically to federal agencies to safeguard controlled unclassified information (CUI). Atomic OSSEC weaves OpenScap and SCAP and Red Hat Ansible security automation capabilities into a network-noninvasive toolset rich with built-in advanced security capabilities and NIST compliance controls. It goes deep into OS resources, disparate connective endpoints, and out to the software supply chain to monitor and protect data and systems. 

Whether it’s PCI-DSS, HIPAA, NIST 800-171, FISMA, FIPS, JSIG, GDPR, or other requirements, compliance requires ongoing effort for which your security and compliance personnel need help. The visibility and control you need for compliance is particularly challenging when doing business in the cloud. When you don’t own the network or infrastructure, you can’t see as much and this is where compliance problems multiply and you can lose track of your data and your customers’ data.

Atomic OSSEC provides advanced and real-time file integrity monitoring (FIM) – critical capabilities for detecting and alerting you to breaches and unauthorized changes in your environment and across cloud interfaces.


Watch the Real-Time FIM Video Demonstration

Timer-based file monitoring is not sufficient for critical IT and OT. Intensify and accelerate file and system behavior analysis and response with the real time FIM in Atomic OSSEC.

Watch real-time FIM in action.

  • Detect malware or a hash which is unique to every single file. Atomic OSSEC provides a fast lightweight way to scan heterogeneous environments and look up hashes.
  • Get an alert. FIM is more alert-oriented than file activity monitoring. FIM is also broader, and scans system files, workstations, databases, operating systems, analyzes and generates alerts.
  • Run a tool against the malware. CLAM AV will not let you write that file and send it out. We do. 
  • Protect inline angles, user browsers, stopping the malware before it reaches the application level.
  • See who changed the file, user name, what they used to get in, the process and server name. Timer-based FIM would not get this info. 
  • Know exactly what the change was. Atomic OSSEC shows which line or lines were modified and on which systems the event occurred. 
  • Catch adds and deletes. This detection capability is advisable over attack surfaces that are typical of malware.
  • Search, correlate and analyze security event data. Our dashboard enables full-text search over all fields and easy drill-in to FIM, PCI DSS, vulnerability detection and anomalous change categories. You can narrow your search to what happened at a specific time frame or moment. 
  • Go to the events themselves. Discover what happened, for example, a file was added to the system and take additional measures if necessary. 


Real-time FIM is just one of the advanced capabilities in the Atomic OSSEC XDR, which equips organizations and federal agencies with log-based IDS, vulnerability management, defense-in-depth lateral protection, active response, and more. 

Watch the Atomic OSSEC overview video demo now.


Try Our Real-Time FIM and More in Free Atomic OSSEC Trial

Atomic OSSEC is a versatile open-source-based XDR that provides deep control over your software, allowing you to detect and thwart attacks that spread laterally or through the software supply chain. Use the solution to:

  • Orchestrate security to virtually any endpoint where activity has to be monitored for protection and compliance, and direct real-time FIM toward your most critical data and system protection use cases.
  • Detect anomalous changes to files down to the line of code (during input and output).
  • Remove malware and ransomware, reduce response times, and keep your code clean.
  • Facilitate compliance with NIST, PCI DSS and JSIG and additional standards and regulations using built in OSSEC FIM and audit control rules, tools and templates.
  • Activate response. Get an infusion of global threat intelligence through OSSEC, ModSecurity, and Atomicorp, and address threats and vulnerabilities with the Atomic OSSEC XDR rules engine.
  • Test your system and more easily detect and manage vulnerabilities.
  • Move beyond the command line toward greater SIEM and compliance with a GUI for security auditing, forensic analysis, reporting and compliance.

Get a Free Atomic OSSEC trial.

Want to try the product for a free 14-day trial period? If you’re ready for an Atomic OSSEC trial, just provide a valid company or organization email address and the number of endpoints you’d like to protect (up to 10). No credit card required for the trial period.

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If you are interested in getting pricing details for Atomic OSSEC before or beyond the trial, please contact us. For certain deployments, we charge less than $5 a server per month; that’s just 15 cents per day to protect your endpoints.

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