Sigma rule: Dfsvc.EXE Initiated Network Connection Over Uncommon Port

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-161b32f5cf03, updated 2024-01-31T00:00:00.000Z.

Rule

Title
Dfsvc.EXE Initiated Network Connection Over Uncommon Port
Status
test
Level
high
Author
Nasreddine Bencherchali (Nextron Systems)
Date
2023-06-12
Modified
2024-01-31
File
rules-threat-hunting/windows/network_connection/net_connection_win_dfsvc_uncommon_ports.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects an initiated network connection over uncommon ports from "dfsvc.exe". A utility used to handled ClickOnce applications.

Log source

product
windows
category
network_connection

Detection

selection:
    Image|contains: ':\Windows\Microsoft.NET\'
    Image|endswith: '\dfsvc.exe'
    Initiated: 'true'
filter_main_known_ports:
    DestinationPort:
        - 80
        - 443
filter_optional_dns_ipv6:
    # Based on VT. More than 140 binaries made communication over DNS
    DestinationIsIpv6: 'true'
    DestinationPort: 53
condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*

False positives (as the rule lists them)

  • Unknown

Tags

  • attack.execution
  • attack.t1203
  • detection.threat-hunting

MITRE ATT&CK ids this rule names

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-threat-hunting/windows/network_connection/net_connection_win_dfsvc_uncommon_ports.yml

Sources and licences

  • SigmaHQ

    "Dfsvc.EXE Initiated Network Connection Over Uncommon Port" by Nasreddine Bencherchali (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-threat-hunting/windows/network_connection/net_connection_win_dfsvc_uncommon_ports.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Dfsvc.EXE Initiated Network Connection Over Uncommon Port",
entity page, dataset version ref-161b32f5cf03, updated 2024-01-31T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/4c5fba4a-9ef6-4f16-823d-606246054741 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 4c5fba4a-9ef6-4f16-823d-606246054741, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.