Managed Risk Scanner FAQ

Frequently Asked Questions

Overview

This document contains frequently asked questions (FAQ) about the Arctic Wolf® Managed Risk® Scanner, including Internal Vulnerability Assessment (iVA) scanning. For more information about scan configuration, see Risk Dashboard User Guide.

Contact your Concierge Security® Team (CST) if you have questions tha tare not covered here.

Scanner installation and configuration FAQs

These are FAQs about installing and configuring the physical and virtual scanner.

Q: Where in the network should I deploy the scanner?

A: You can place the scanner anywhere within the network to scan any device that has layer 3 (L3) reachability. If the scanner can ping a device, it can scan that device. This includes off-site devices that are connected to the customer network through VPN.

Q: Who installs the scanner?

A: An Arctic Wolf employee and your IT staff install the scanner, depending on whether the customer chooses the virtual machine (VM) or physical scanner.

Q: Who maintains the scanner?

A: Arctic Wolf owns the scanner hardware or VM software instance provided to enable network discovery of threats and vulnerabilities. Therefore, Arctic Wolf maintains scanner service, including regular software updates and scanner warranty.

Q: How long does the hardware scanner installation take?

A: The physical installation takes minutes. To physically install the hardware scanner, you need to rack mount the scanner, and connect an ethernet cable and power cord.

Once powered on, the scanner connects to Arctic Wolf servers within minutes.

Q: What are the physical space and power requirements of the hardware scanner?

A: The physical scanner hardware is a 1RU rack-mountable server with these dimensions in inches: 1.7 high x 16.8 wide x 14.0 deep. A 200-W, low-noise AC power supply with power factor correction (PFC) powers the scanner.

Q: Does the physical scanner support scanning multiple non-routable networks?

A: No, even though the physical scanner has multiple hardware network ports, the software is only configured to allow one primary network, or one network interface card (NIC). Multiple physical, non-routable networks are not supported because that configuration would cause the scanner itself to become a bridge between networks that are otherwise wholly separated, which is a violation of secure design principles.

Q: Do I need to configure the scanner?

A: The scanner can search for hosts on its network and begin scanning without configuration. You can also easily configure the scanner to scan or ignore any other routable host(s) or network(s), if desired.

Q: Do I need to open a port in the firewall for the scanner?

A: The scanner, both physical and virtual, communicates to the Arctic Wolf cloud infrastructure. We recommend that you create a defined outbound security rule from the scanner IP address to all necessary Arctic Wolf scanner IP addresses to ensure proper functionality. See Arctic Wolf IP Addresses on the Arctic Wolf Portal for complete details.

Q: Can I have multiple scanners for different parts of my network?

A: Yes, you can deploy multiple scanners to scan separate parts of your network, such as a co-lo or remote office which do not have direct connectivity, or you otherwise do not want to scan from the location of the main Ssanner.

Q: Can we configure our own NTP server for the scanner?

A: No, you cannot configure your own NTP server for the scanner. The scanner is configured to reach out to a pool of global, publicly available NTP servers. This is to ensure consistency in case of localized issues.

Q: What virtual environments are supported for the virtual scanner?

A: See Managed Risk Virtual Scanner Installation for all requirements.

Q: Is it normal for my virtual machine to use a lot of CPU resources?

A: The scanner virtual machine (VM) is designed to scan continuously and as fast as it can to go through all the hosts on the network as quickly as possible. As such, it is normal for the scanner to consume all of the vCPUs allocated to it. In a highly overloaded ESXi environment, this may not be desirable, and allocating more resources may be difficult in the short term. In this situation, we recommend using the minimum system requirements as described in Managed Risk Virtual Scanner Installation.

If CPU consumption is an issue, try:

Q: What kind of impact does the scanner have on the network and systems?

A: The network scanner primarily uses two tools to detect hosts and conduct vulnerability scans:

The actual impact of processing on the target systems is typically negligible. Some older systems, such as consumer-grade printers or network Internet-of-Things (IoT) devices, may have denial of service vulnerabilities that are revealed when scanned.

Scanner operation FAQs

These are FAQs about scanner operation, including scan recommendations.

Q: What tests does the scanner perform?

A: The scanner runs network vulnerability tests (NVTs) that provide:

Q: What does the scanner do during a scan?

A: Using the provided schedules, the scanner gets the list of targets to look for. Using the list of targets and the data from the DenyList, it attempts to determine if relevant machines are online by sending out Address Resolution Protocol (ARP), Internet Control Message Protocol (ICMP), and Transmission Control Protocol (TCP) packets and monitoring for any responses.

In almost all cases, the scanner runs a full scan that:

Q: What kind of devices does the scanner scan?

A: The scanner can scan all device types on a network, including networking gear like switches and routers, printers, cameras, phones, and so on. However, scanning some devices can cause unintended behaviours, including significant issues to production environments if the scanner is configured to scan specific devices. Therefore, we recommend scanning only workstations and servers.

Here are some devices to avoid scanning:

Q: Does the scanner scan over IPv6 networks?

A: No, the scanner does not support scanning over IPv6 networks.

Q: Does the scanner exploit found vulnerabilities?

A: These are the types of network tests that the scanner runs:

Note: The scanner never exploits a vulnerability discovered on a host. The scanner determines if a vulnerability exists and then drops the connection to that host or service.

Q: How resource-intensive is the scan on the target machine?

A: Managed Risk scans have a very low impact. Users should not notice any impact on the target machine during scanning.

Q: Should I stagger scan times based on location?

A: You can configure scans based on your preference, including location. You may prefer to perform workstation scanning during the day and server scanning overnight. Scans always run in the order that they are listed on the Risk Dashboard. See Risk Dashboard User Guide for more information.

Q: When is continuous scanning applicable or preferred?

A: Continuous scanning enables continuous visibility and the immediate discovery of new devices and vulnerabilities that enter the network.

Continuous scanning is applicable to iVA scanning and host-based scanning, and is a preferred method because it provides insight that point-in-time vulnerability scans do not. Specifically, things happen in between those point-in-time scans that are missed if you are not continuously scanning.

Q: Are there best practices for scan schedules?

A: We suggest starting the scans when a member of the your team is available. That way, you can add devices to the DenyList or turn off scanning if a host reacts poorly to being scanned. Scanning schedules should help prevent devices from going offline or prevent scanners from overwhelming devices with HTTP requests during business hours.

Q: How long does a typical scan take per device?

A: The scan can take up to an hour to complete but is usually faster. Scan time depends on the number of open ports and network vulnerability tests (NVTs) that the scan runs against the host. By default, six hosts can be scanned at the same time.

Note: After two hours, scans timeout so they quit scanning that particular asset.

Q: How should I configure the scanning schedule?

A: You should only configure private internal IP addresses for the scanner to scan. Do not add anything outside of the ranges listed here: https://en.wikipedia.org/wiki/Private_network.

Note: An IP range such as 192.168/16 is the internal space, whereas 192.11.1.1 is a public internet address, and should not be configured to be scanned.

We recommend scanning subnet ranges /24 and smaller, excluding /8, /16, or /20. Scanning these large subnet ranges would likely cause a timeout issue.

With the assumption that each scan takes about 12 minutes to complete per device, this table provides estimates for how long it takes to scan specific subnet sizes:

CIDR Subnet mask Total IP addresses Minutes to scan Hours to scan
/32 255.255.255.255 1 12 0.2
/31 255.255.255.254 2 24 0.4
/30 255.255.255.252 4 48 0.8
/29 255.255.255.248 8 96 1.6
/28 255.255.255.240 16 192 3.2
/27 255.255.255.224 32 384 6.4
/26 255.255.255.192 64 768 12.8
/25 255.255.255.128 128 1536 25.6
/24 255.255.255.0 256 3072 51.2
/23 255.255.254.0 512 6144 102.4
/22 255.255.252.0 1024 12288 204.8
/21 255.255.248.0 2048 24576 409.6
/20 255.255.240.0 4096 49152 819.2
/19 255.255.224.0 8192 98304 1638.4
/18 255.255.192.0 16,384 196608 3276.8
/17 255.255.128.0 32,768 393216 6553.6
/16 255.255.0.0 65,536 786432 13107.2
/15 255.254.0.0 131,072 1572864 26214.4
/14 255.252.0.0 262,144 3145728 52428.8
/13 255.248.0.0 524,288 6291456 104857.6
/12 255.240.0.0 1,048,576 12582912 209715.2
/11 255.224.0.0 2,097,152 25165824 419430.4
/10 255.192.0.0 4,194,304 50331648 838860.8
/9 255.128.0.0 8,388,608 100663296 1677721.6
/8 255.0.0.0 16,777,216 201326592 3355443.2
/7 254.0.0.0 33,554,432 402653184 6710886.4
/6 252.0.0.0 67,108,864 805306368 13421772.8
/5 248.0.0.0 134,217,728 1610612736 26843545.6
/4 240.0.0.0 268,435,456 3221225472 53687091.2
/3 224.0.0.0 536,870,912 6442450944 107374182.4
/2 192.0.0.0 1,073,741,824 12884901888 214748364.8
/1 128.0.0.0 2,147,483,648 25769803776 429496729.6

Q: What is the difference between the default discovery scans, like Nmap, and a ping-only scan?

A: The default Nmap scan is used to find what hosts exist, which we should scan for vulnerabilities. The tests performed include:

Enabling Ping Only mode restricts host detection scans to the use of only ICMP echo, which means that hosts that do not respond to a ping are not detected.

Q: Does the scanner scan for or detect the SSL/TLS versions that a website supports?

A: The scanner looks for weak TLS ciphers. It does not look at SSL registry information or test against failback methods.

Q: Why is the scanner failing to resolve a host name?

A: The scanner does not perform asset profiling, including host name resolution if:

If you are seeing continued failures to resolve the name for a visible host, contact Arctic Wolf so that we can attempt manual tests on the scanner.

Note: We recommend adding all DNS servers to the Host Collection DNS Servers in the Risk Dashboard.

iVA scanning FAQs

These are FAQs about iVA scanning.

Q: Does the iVA Scanner scan for common passwords like “admin” or “password” to see if any devices have default or easily guessable passwords on them?

A: There is an option on the iVA Scanner to perform brute-force scans, where common or default usernames and passwords are attempted. We limit the number of passwords attempted to the most common ones, and tailor the list based on the type of device detected to limit causing account lockouts. Additionally, Managed Risk (MR) performs Account Takeover (ATO) scans to identify instances of passwords, credentials, or other personally identifiable information (PII) that were exposed to malicious actors.

Q: If scheduled scans are configured, why is host identification scanning occurring outside of the schedule?

A: The iVA Scanner maintains an active list of all targets and decides the targets and order for scanning during the scheduled vulnerability scan, based on the latest results. Host identification scanning is permitted outside of the vulnerability scanning window so that it does not limit the time remaining in the scheduled window for vulnerability scans.

Q: How are the credentials that are used in credential scanning stored?

A: When a sensor first comes online and registers with our system, it generates a unique public/private cryptographic key pair using RSA with a 4096-bit key. Part of the registration process for the new sensor is to publish the public component of this key pair to our servers. The private key is never transmitted off of the sensor.

When a credential is added through the Risk Dashboard for credentialed scanning, the data is divided into public and private fields. Public fields include things such as the hosts that a given credential is for, the display name of the credential that is not the username, and a comment for easy viewing on the Risk Dashboard. Private fields include usernames, passwords, certificates, keys, and any information that could be used as a component of the actual credential.

The private fields are encrypted with a unique AES 256 key, or session key, which is in turn encrypted with the public key of a target sensor. This encrypted data package is then paired with the public fields and stored in our database. A copy of this data is sent to the target sensor over a secure channel that again uses unique AES 256 session keys secured with the sensor public key.

The public information is stored in the database for use with the Risk Dashboard, and the private information is stored for re-publishing to the sensor if the sensor ever requests it. Once stored in the database, there is no way for any device other than the sensor to read the private fields of a credential, and they cannot be recovered or moved to another sensor.

When the sensor receives the encrypted credential message, the message is stored to disk using the existing encryption before it is decrypted, and then it is decrypted only as required during use. It is never stored on disk in a decrypted form.

Q: Does vulnerability scanning work if asset identification scanning is disabled?

A: No, you must enable asset identification scanning to perform vulnerability scanning. You can make these adjustments on the Scanner Config page of the Risk Dashboard. See Risk Dashboard User Guide for more information.

Q: How long does it take to scan my environment with continuous scanning?

A: As a rough guideline, the Arctic Wolf 200 series physical scanner and the virtual scanner can scan approximately 150 devices in a 24-hour period. The 100 series physical scanners scan approximately 75 devices in a 24-hour period.

If you limit the scan window and you have a lot of devices to scan, the scan may never fully complete in the time window that you set. Since a scan can range from 2–200 minutes, we do not terminate scans at the end of a window to prevent a situation where some longer-running scans never complete. For example, if a customer sets several 60-minute windows and they have a host that takes 70 minutes to scan, the scan always fails. So we define the start of the scan, relying on the fact that the majority of scans take only 5-15 minutes to complete.

Q: Can I scan AWS or other cloud-hosted devices?

A: Various cloud providers have different policies around when and if vulnerability assessments are allowed according to their respective Acceptable Use Policies (AUPs):

Q: Can we schedule iVA scans of devices or IP addresses on a daily, monthly, or quarterly basis?

A: You can schedule iVA scans to run monthly, weekly, daily, or continuously. This frequency is configurable on a network-by-network or host-by-host basis.

Q: What is the underlying technology used for iVA scanning?

A: OpenVas is the underlying technology used for iVA scanning.

Note: Arctic Wolf uses a variety of effective cybersecurity technologies to ensure the security of our customers. Therefore, underlying technologies may change over time as other technologies become available.

EVA scanning FAQs

These are FAQs about External Vulnerability Assessment (EVA) scanning.

Q: How many ports are scanned during an EVA scan?

A: The Nmap or EVA scan uses the top 1,000 common ports. See [https://nmap.org/book/port-scanning.html#most-popular-ports](Nmap Network Scanning Overview) on the Nmap website for more information.

Q: How does the EVA Scanner determine if a host is online before performing a vulnerability scan?

A: The EVA Scanner uses the results of an initial Nmap scan confirm that we received port information, even if the ports are reportedly closed, and then proceeds with the EVA scan.

Q: How often are discovery scans run?

A: An Nmap scan runs every 5 minutes to re-map the network to account for any new devices or changes in the current environment. The results of that Nmap scan are sent to OpenVAS, which then begins a full-fast scan of the detected devices.

Q: Can we schedule EVA scans of devices or IP addresses on a daily, monthly, or quarterly basis?

A: By default, we run EVA scans on a monthly basis. You can adjust the frequency of EVA scans to weekly, but we do not recommend this approach because it increases the risk of firewall bans from generating too much noise.

Scanner troubleshooting FAQs

These are FAQs about scanner troubleshooting.

Q: Why does the scanner show results for itself in the Risk Dashboard?

A: If the scanner IP address is not added to the AllowList on the Scanner Config page of the Risk Dashboard, the scanner IP address can appear in scan results in the Risk Dashboard. See the IP addresses listed under If you are a Managed Risk (MR) customer on the Arctic Wolf IP Addresses page in the Arctic Wolf Portal.

Q: Why did I see a bandwidth spike during a scan?

A: Spikes in bandwidth usage may be related to:

See also