Sigma rule: BITS Transfer Job With Uncommon Or Suspicious Remote TLD

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-92b26a2c6ad6, updated 2025-02-28T00:00:00.000Z.

Rule

Title: BITS Transfer Job With Uncommon Or Suspicious Remote TLD
Status: test
Level: medium
Author: Florian Roth (Nextron Systems)
Date: 2022-06-10
Modified: 2025-02-28
File: rules/windows/builtin/bits_client/win_bits_client_new_transfer_via_uncommon_tld.yml
Commit: ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects a suspicious download using the BITS client from a FQDN that is unusual. Adversaries may abuse BITS jobs to persistently execute or clean up after malicious payloads.

Log source

product: windows
service: bits-client

Detection

selection:
    EventID: 16403
filter_main_generic:
    RemoteName|contains:
        - '.azureedge.net/'
        - '.com/'
        - '.sfx.ms/'
        - 'download.mozilla.org/' # https://download.mozilla.org/?product=firefox-101.0.1-partial-101.0&amp;os=win64&amp;lang=en-US
        - 'cdn.onenote.net/'
        - 'cdn.office.net/'
        - 'tscdn.m365.static.microsoft/'
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

This rule doesn't exclude other known TLDs such as ".org" or ".net". It's recommended to apply additional filters for software and scripts that leverage the BITS service

MITRE ATT&CK ids this rule names

T1197

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/windows/builtin/bits_client/win_bits_client_new_transfer_via_uncommon_tld.yml

Sources and licences

SigmaHQ
"BITS Transfer Job With Uncommon Or Suspicious Remote TLD" by Florian Roth (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/builtin/bits_client/win_bits_client_new_transfer_via_uncommon_tld.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: BITS Transfer Job With Uncommon Or Suspicious Remote TLD",
entity page, dataset version ref-92b26a2c6ad6, updated 2025-02-28T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/6d44fb93-e7d2-475c-9d3d-54c9c1e33427 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 6d44fb93-e7d2-475c-9d3d-54c9c1e33427, 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.