Indicators of Compromise : How To Prevent Cyber Threats?
Oct 22, 2021
Indicators of Compromise : How To Prevent Cyber Threats?

What is IOC?

Indicators of Compromise(IOCs) are forensic indicators of possible intrusions on a host system or network that detect potentially malicious activity on the machine or network.

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Where can we find IOCs?
IOC artifacts can be found in the system's event logs and time stamped entries, as well as its applications and services.

Why is it hard to detect an IOC?
IOCs can range from simple information items to more complicated malicious code and content samples, and so they're not always easy to spot.

Significance of IOCs

IoCs (Indicators of Compromise) are indicators that a cyber-attack has occurred. IoCs provide useful information about what happened, but they can also be used to plan for future attacks and prevent them. Antimalware software and other security solutions proactively guard against evasive threats by using established indicators of compromise, such as a viral signature. Heuristic analysis can also make use of IOCs.

How Does It Help Organizations?

Information security and IT workers can use indicators of compromise to detect data breaches, malware infections, and other threats. Organizations can detect attacks and act fast to avoid breaches or limit the damage by detecting attacks in the early stages by monitoring the indicators of compromise.

IOCs are used by security researchers to better understand a malware's strategies and behavior. IOCs also give actionable threat intelligence that may be shared across community members to help them improve.

How Does It Act As A Means To Detect Malicious Activity?

IOCs can help information security and IT professionals to detect malicious behavior early in the attack chain. These unusual activities are red flags that suggest a possible or ongoing attack that could result in a data breach or a system compromise.

Why Should Organizations Monitor IOC's?

IOCs can aid in improving detection accuracy and speed, as well as the time it takes to remediate a problem. The earlier an attack is detected, the less influence it will have on the company's business and the easier it will be to handle. IOCs, particularly those that are reoccurring, give the company a window into their adversaries' strategies and methodologies. As a result, organizations can use these insights to improve their security tooling, incident response skills, and cyber security policies in order to avoid repeat incidents.

Improved Detection and Response Through Indicators of Compromise

Following an incident, IoC cyber security measures can be employed to figure out what went wrong and prevent future exploits of the same vulnerability. Organizations can fail to appropriately log and monitor the appropriate resources. As a result of this error, they are vulnerable to an attacker who can then evade notice after an inquiry. It's critical to use network monitoring to detect an attack initially, but logs and audit trails are just as crucial for investigations. To reduce reaction time during an inquiry, IoC data points can be acquired in real time. SIEMs are used to remove noise from important evidence that is needed to identify an attack and its consequences.

Documenting current incident response protocols can also help speed up the investigative process. Following a compromise, these procedures should be examined in order to enhance them. The "lessons learned" phase is the final step in the incident response process. During this phase, IoCs can help discover which cyber security defenses were installed incorrectly or were insufficient to stop an attacker. The more detailed logs and audit trails a business has, the more effective its incident response investigation will be.

IOC Monitoring

Because IOC monitoring is reactive, if an organization discovers an indicator, it is almost clear that they have already been hacked. However, if the event is already underway, early identification of an IOC may be able to assist contain attacks earlier in their lifetime, limiting their impact on the organization.

How To Identify IOC's?

The cybercriminal will leave evidence of their activity in the system and log files if a company is an attack target or victim. The threat hunting team will collect digital forensic data from these files and systems in order to assess if a security threat or data breach has happened or is currently taking place. Analysts often detect a large number of IOCs in order to look for trends and piece them together to analyze a potential danger or occurrence. Investigators can manually collect indicators of breach after seeing questionable activity, or they can do it automatically as part of the company's cyber security monitoring capabilities.

IOC and Threat Analysis

Threat analysis can assist you in figuring out which factors to link to a certain threat. The IoCs linked to a danger are first recognized. Later on, the compromise indications will be used to track down risks in an organization's infrastructure. When an IoC is discovered on a system, it means the system is most likely under assault, necessitating the use of specific countermeasures. The databases of passive monitoring tools and antivirus software, which can detect infiltration attempts, are also updated with indicators of compromise.

IOC's vs. Indicators of Attack

IOC focuses on forensic investigation of a previously compromised system to help answer the question "What happened?". OA's focus on detecting attacker activity during an attack helps answer questions like "What is happening and why?".

Using both IOAs and IOCs to identify security issues or threats in as near to real time as possible would be a proactive method to detecting risks.

A Typical User and an IOC

Many Internet services alert account holders when a strange device or IP address from another country attempts to log in. Users should take such communications seriously, double-check the information included inside, and change their passwords immediately if any of the actions stated appear suspect.

Examples of IOC's, We Need To Watch Out For:

Typical IoCs are virus signatures and IP addresses, MD5 hashes of malware files, or URLs or domain names of botnet command and control servers, registry key and filename. We should be aware of the following IOCs:

  • Unusual network traffic entering and exiting
  • Suspicious activity in administrator or privileged accounts
  • Unknown files, apps, and processes in the system
  • Irregular activities, such as traffic from countries where the company does not do business
  • Suspicious log-ins, access, and other network activities, which could suggest probing or brute-force attacks.
  • Unusual jumps in request traffic and read volume in corporate files
  • Network traffic that passes through ports that aren't often used
  • Changes in system settings, including those on mobile devices, as well as tampered files, DNS, and registry configurations
  • A lot of compressed files and data found in locations where they shouldn't be

IOC Deliberations

According to some in the industry, documenting IOCs and threats helps organizations and people communicate knowledge among the IT community and better incident response and computer forensics. The OpenIOC framework is one way to express malware analysis results systematically. STIX and TAXII, for example, are working to standardize IOC documentation and reporting.


Each company's threat intelligence teams should detect IOCs, raise incidents, monitor the status, investigate the danger, and endeavor to close the gap. A cyber security red team should be notified if the gap is not closed. They can help close the gap and prevent more data loss.

In the fight against malware and cyber attacks, indicators of compromise are essential. While reactive in nature, businesses that constantly monitor for IOCs and stay up with the newest IOC discoveries and reporting can greatly improve detection rates and reaction timelines.