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Network Service Scanning

Adversaries may attempt to get a listing of services running on remote hosts, including those that may be vulnerable to remote software exploitation. Methods to acquire this information include port scans and vulnerability scans using tools that are brought onto a system.

ID: T1046

Tactic: Discovery

Platform:  Linux, Windows, macOS

Permissions Required:  Administrator, SYSTEM, User

Data Sources:  Netflow/Enclave netflow, Network protocol analysis, Packet capture, Process command-line parameters, Process use of network

Version: 1.0

Examples

NameDescription
BlackEnergy

BlackEnergy has conducted port scans on a host.[1]

Cobalt Group

Cobalt Group leveraged an open-source tool called SoftPerfect Network Scanner to perform network scanning.[2][3][4]

Cobalt Strike

Cobalt Strike can perform port scans from an infected host.[5]

FIN6

FIN6 used publicly available tools (including Microsoft's built-in SQL querying tool, osql.exe) to map the internal network and conduct reconnaissance against Active Directory, Structured Query Language (SQL) servers, and NetBIOS.[6]

HDoor

HDoor scans to identify open ports on the victim.[7]

Koadic

Koadic can scan for open TCP ports on the target network.[8]

Leafminer

Leafminer scanned network services to search for vulnerabilities in the victim system.[9]

menuPass

menuPass has used tcping.exe, similar to Ping, to probe port status on systems of interest.[10]

MURKYTOP

has the capability to scan for open ports on hosts in a connected network.[11]

OilRig

OilRig has used the publicly available tool SoftPerfect Network Scanner as well as a custom tool called GOLDIRONY to conduct network scanning.[12]

Pupy

Pupy has a built-in module for port scanning.[13]

Remsec

Remsec has a plugin that can perform ARP scanning as well as port scanning.[14]

Suckfly

Suckfly the victim's internal network for hosts with ports 8080, 5900, and 40 open.[15]

Threat Group-3390

Threat Group-3390 actors use the Hunter tool to conduct network service discovery for vulnerable systems.[16]

XTunnel

XTunnel is capable of probing the network for open ports.[17]

Mitigation

Use network intrusion detection/prevention systems to detect and prevent remote service scans. Ensure that unnecessary ports and services are closed and proper network segmentation is followed to protect critical servers and devices.

Identify unnecessary system utilities or potentially malicious software that may be used to acquire information about services running on remote systems, and audit and/or block them by using whitelisting [18] tools, like AppLocker, [19] [20] or Software Restriction Policies [21] where appropriate. [22]

Detection

System and network discovery techniques normally occur throughout an operation as an adversary learns the environment. Data and events should not be viewed in isolation, but as part of a chain of behavior that could lead to other activities, such as Lateral Movement, based on the information obtained.

Normal, benign system and network events from legitimate remote service scanning may be uncommon, depending on the environment and how they are used. Legitimate open port and vulnerability scanning may be conducted within the environment and will need to be deconflicted with any detection capabilities developed. Network intrusion detection systems can also be used to identify scanning activity. Monitor for process use of the networks and inspect intra-network flows to detect port scans.

References