PUA - NimScan Execution

testmedium
Log-Quelle: windows · process_creationAutor Swachchhanda Shrawan Poudel (Nextron Systems)Datum 2025-02-05
01

Beschreibung

Was dies ist, in Kürze.

Detects usage of NimScan, a portscanner utility. In early 2025, adversaries were observed using this utility to scan for open ports on remote hosts in a compromised environment. This rule identifies the execution of NimScan based on the process image name and specific hash values associated with different versions of the tool.

02

Tags

attack.discoveryattack.t1046
03

Regelquelle (YAML)

title: PUA - NimScan Execution
id: 4fd6b1c7-19b8-4488-97f6-00f0924991a3
status: test
description: |
    Detects usage of NimScan, a portscanner utility.
    In early 2025, adversaries were observed using this utility to scan for open ports on remote hosts in a compromised environment.
    This rule identifies the execution of NimScan based on the process image name and specific hash values associated with different versions of the tool.
references:
    - https://x.com/cyberfeeddigest/status/1887041526397587859
    - https://github.com/elddy/NimScan
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-02-05
tags:
    - attack.discovery
    - attack.t1046
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - Image|endswith: '\NimScan.exe' # Other metadata fields such as originalfilename and product were omitted because they were null
        - Hashes|contains:
              - 'IMPHASH=41BB1C7571B3A724EB83A1D2B96DBB8C' # v1.0.8
              - 'IMPHASH=B1B6ADACB172795480179EFD18A29549' # v1.0.6
              - 'IMPHASH=0D1F896DC7642AD8384F9042F30279C2' # v1.0.4 and v1.0.2
    condition: selection
falsepositives:
    - Legitimate administrator activity
level: medium
04

erkennt Techniken (1)

ATT&CK-Techniken, die dies ermöglicht oder abbildet.

05

Referenzen

Externe Belege — Patches, Meldungen, Analysen.