LoFP LoFP / legitimate sccm upgrades or hotfix installations may create or replace adsource.dll in the bin\x64 directory. validate the file hash and digital signature of any detected adsource.dll against the expected version for the installed sccm build before tuning.

Techniques

Sample rules

Windows SCCM Adsource DLL Was Planted In SMS Provider Directory

Description

The following analytic detects the creation or modification of adsource.dll or other staging files with the name adsource_*.dll within the SCCM SMS Provider bin directory, consistent with exploitation of CVE-2026-47301. This abuses a DLL side-loading vulnerability in the Microsoft Configuration Manager SMS Provider component. An attacker can plant a malicious adsource.dll in the SCCMProvider bin\X64 path, causing the SMS Provider service to load the attacker-controlled library in a privileged context. The presence of renamed dlls alongside adsource.dll is a strong indicator of the classic DLL hijacking pattern where the legitimate library has been renamed so the malicious replacement can proxy calls to it. If confirmed malicious, this activity represents a privilege escalation vector that can result in SYSTEM-level code execution on any host running the SCCM SMS Provider role.

Detection logic


| tstats `security_content_summariesonly`
  count min(_time) as firstTime
        max(_time) as lastTime

from datamodel=Endpoint.Filesystem where

Filesystem.action IN ("created", "modified")
Filesystem.file_name IN (
    "adsource.dll",
    "adsource_*.dll"
)
Filesystem.file_path="*Microsoft Configuration Manager\\bin\\X64\\*"

BY Filesystem.action Filesystem.dest Filesystem.file_access_time
    Filesystem.file_create_time Filesystem.file_hash Filesystem.file_modify_time
    Filesystem.file_name Filesystem.file_path Filesystem.file_acl
    Filesystem.file_size Filesystem.process_guid Filesystem.process_id
    Filesystem.user Filesystem.vendor_product


| `drop_dm_object_name(Filesystem)`

| `security_content_ctime(firstTime)`

| `security_content_ctime(lastTime)`

| `windows_sccm_adsource_dll_was_planted_in_sms_provider_directory_filter`