Active Scanning in Cybersecurity – Everything You Need to Know
In the previous article, we discussed the MITRE ATT&CK framework which consists of several tactics and techniques based on real-world observation. Reconnaissance is one of the tactics. Further, it is composed of 10 different techniques and Active Scanning is one of them.
So, here we’ll cover the topic of active scanning, associated sub-techniques, and different special active scans in detail.
Let’s dig deeper and discuss some facts about active scanning in cybersecurity.
What is Active Scanning and Why Is It Used?
Active scanning is a scanning technique in which you scan specific endpoints in an IT network to gather more precise data. Instead of passively gathering that information by “catching” it on the network’s traffic, active scanning involves sending packets or queries directly to certain assets. Simply described, active scanning is a rapid deep scan performed on chosen targets to gather incredibly detailed data. These targets may be individual or collective devices.
It is used to locate, monitor, and administer IT or OT assets. In addition to gathering fundamental asset data, it also gathers specific information about users, installed software, patch levels, and other things. It is helpful for a wide range of use cases, including vulnerability analyses, compliance audits, and other ITAM and SAM-related duties. For instance, a device that hasn’t had an update in a long or that someone who shouldn’t be accessing it is using. Therefore, these scans are perfect for aiding in asset investigations and enhancing a network’s cybersecurity.
Active Scanning as per MITRE ATT&CK Framework
When adversaries target an organization, they may execute active reconnaissance scans to gather information. They may probe victim infrastructure using active scans via network traffic, as opposed to other forms of reconnaissance that do not involve direct interaction.
There are different forms that adversaries may use to perform active scanning based on what information they want to gather. These scans can also be carried out in a variety of methods, such as by utilizing the built-in functionality of network protocols like ICMP. These scans may provide chances for additional forms of reconnaissance, such as searching publicly accessible websites and databases, building operational resources, such as developing or acquiring capabilities, and/or gaining first access (ex: External Remote Services or Exploit Public-Facing Applications).
Mitigation and Detection in Active Scanning
The term “Pre-Compromise” is used for any eligible mitigating actions that relate to methods employed before an adversary has Initial Access.
Active Scanning technique cannot be easily mitigated with preventive controls since it is based on behaviors performed outside of the scope of enterprise defenses and controls. Efforts should concentrate on reducing the volume and sensitivity of data that is accessible to outside parties.
In detection, the data source is “Network Traffic” which has two data components i.e. Network Traffic Content (NTC) and Network Traffic Flow (NTF). NTC monitors and analyzes traffic patterns and packet inspection associated with protocol(s) that do not follow the expected protocol standards and traffic flows. And, NTF monitors network data for unusual data flows.
Sub-Techniques of Active Scanning
There are three sub-techniques associated with active scanning. They are;
- Scanning IP Blocks
- Vulnerability Scanning
- Wordlist Scanning
Let’s briefly discuss the above sub-techniques.
1. Scanning IP Blocks
If you try to understand the concept from the attacker’s point of view, then they may scan IP blocks to gather information about victim networks, such as which IP addresses are in use as well as more specific details about the hosts assigned to those IP addresses. These scans may include and range from simple pings (ICMP requests and responses) to more nuanced scans that may reveal host software/versions via server banners or other network artifacts.
2. Vulnerability Scanning
The attackers may try to scan the target’s IT environment for vulnerabilities. They basically check if the configuration of a target/host application properly aligns with the target of a specific exploit they may seek to use.
These scans are attempted to identify any commonly known or exploitable vulnerability present in the current environment. By using server banners, listening ports, or other network artifacts, vulnerability scans often collect information about currently running software and version numbers.
3. Wordlist Scanning
Infrastructure may be iteratively probed by adversaries using brute force and crawling methods. While using techniques similar to those used in brute force, this strategy aims to identify content and infrastructure rather than legitimate credentials.
The wordlists utilized in these scans may include terms pertaining to a particular piece of software as well as generic, frequently used names and file extensions. Adversaries may also use information obtained via various Reconnaissance techniques to construct unique, target-specific wordlists.
Know the Special Active Scans
There are two special active scans present. One is a Diagnostic Scan and the other is Remediation Scan.
Diagnostic Scan assists with troubleshooting, downloading the diagnostic file and sending it to Tenable support. Whereas the remediation scan runs a follow-up active scan against existing active scan results. It evaluates a specific plugin against a specific target or targets where the related vulnerability was present in your earlier active scan.
Advantages of Performing Active Scanning
Smart IT managers are aware that completing security audits once a year is not sufficient since hackers are continually finding new ways to invade networks. Modern best practices recommend continuous monitoring i.e. active scanning to get a real-time perspective of networks and systems.
By executing active scanning, you will be aware of your organization’s entire attack surface and will be one step ahead of the hackers.
Q- Within the context of network security, what is active scanning?
The proactive process of sending network traffic or probes to find and evaluate devices, services, and vulnerabilities within a network is known as “active scanning.” This is done in order to find security flaws before bad actors may take advantage of them.
Q- What distinguishes passive scanning from active scanning?
Sending queries or probes directly to target systems is known as active scanning, and it can be more intrusive. By monitoring network traffic, passive scanning, on the other hand, gathers data without actively probing the target.
Q- What are active scanning’s main objectives?
Finding open ports, susceptible services, security misconfigurations, and potential gaps in the network’s defenses are the principal objectives of active scanning.
Q- Is it morally and legally acceptable to scan?
If done properly and in accordance with applicable laws and regulations, active scanning can be both ethically and legally acceptable. Malicious or unauthorized active scanning may be against the law and immoral.
Q- When does one usually employ active scanning?
Routine security assessments, penetration testing, vulnerability management, compliance checks, and network inventory management are just a few uses for it.
Q- How can businesses lessen the dangers associated with active scanning?
Organizations can reduce risks by obtaining the necessary authorization, using non-disruptive scanning methods, and scheduling scans for maintenance windows or times when there is less traffic. They must have a procedure in place for dealing with unforeseen problems as well.
Q- What are the recommended procedures for carrying out active scanning?
To reduce false positives, best practices include getting express consent, outlining the parameters and guidelines, scanning in a controlled setting, and routinely patching and updating scanning equipment.
Q- How do businesses sort through the results of active scanning and make the necessary corrections?
After determining the risk and potential impact of the findings, organizations should prioritize them and then set up a clear remedial procedure. Patching, resetting systems, or adding further security measures could all be necessary for this.