Windows Alternate Data Stream Created Over Local Share
The following analytic detects the creation of an NTFS alternate data stream (ADS) accessed over a local administrative share targeting the loopback address (127.0.0.1). It leverages Windows Security Event Logs with…
Description
The following analytic detects the creation of an NTFS alternate data stream (ADS) accessed over a local administrative share targeting the loopback address (127.0.0.1). It leverages Windows Security Event Logs with EventCode 5145 to identify this activity. Legitimate local processes access files directly rather than through a local SMB share. This behavior is a hallmark of the ShieldBreak exploit, which abuses a symbolic link swap through a loopback share to redirect a privileged, Defender-driven write into an alternate data stream on a system-owned file, ultimately landing attacker content in C:\Windows\System32. If confirmed malicious, this activity indicates an in-progress local privilege escalation attempt and should be investigated immediately.
Detection logic
Detection requirements
- Platform
- Windows
The rule states no platform. This is derived from the 2 ATT&CK techniques it maps to.
- Log source category
- windows_event_log_security_5145
Known benign triggers
- Backup, replication, or file-sync software may occasionally write alternate data streams over administrative shares. Loopback (127.0.0.1) access to a local share is rare for legitimate software, tune by ShareName or src_user as needed for your environment.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| www.cyderes.com/howler-cell/rogueplanet-windows-zero-day | 7 |
| www.threatlocker.com/blog/nightmareeclipse-releases-new-poc-shieldbreak-exploits-same-weakness-as-rogueplanet | 6 |
From the source
- At source
- Open at source
- Upstream identifier
- e974a5c9-cbe9-4b4a-8fba-b55e7dbc8259
- Tagged by the source as
- RoguePlanetEndpointendpointSplunk CloudSplunk EnterpriseSplunk Enterprise Securityendpoint
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Oct 2, 2026
- Version
- 2