Sysmon Event ID 28: FileBlockShredding
- Applicable version
- Sysmon with this event enabled
- Last reviewed
- 2026-07-22
Quick summary
Sysmon Event ID 28 records that Sysmon detected and blocked file shredding behavior.
Technical Metadata
| Event ID | 28 |
|---|---|
| Provider | Microsoft-Windows-Sysmon |
| Channel | Microsoft-Windows-Sysmon/Operational |
| Level | Informational |
| MITRE ATT&CK | TA0005 Defense Evasion / T1070.004 Indicator Removal: File Deletion |
| Key fields to watch | TargetFilename, Image / ProcessGuid, Hashes |
Trigger Scenarios
Microsoft documents that this event is generated when Sysmon detects and blocks file shredding from tools such as SDelete.
Key Fields
TargetFilename
The file targeted for shredding. Prioritize logs, tools, archives, and payloads in user-writable or temporary paths.
Image / ProcessGuid
The process that attempted shredding and the join key to Event ID 1.
Hashes
Hash values, when present, support triage of the file targeted for destruction.
Threat Hunting Queries
Event
| where EventLog == "Microsoft-Windows-Sysmon/Operational" and EventID == 28
| project TimeGenerated, Computer, EventID, RenderedDescription
| order by TimeGenerated desc- Data source
- Microsoft Sentinel Event table
- Assumptions
- The Sysmon Operational channel is collected into Event. Map raw XML fields to the event-specific fields described on this page.
index=sysmon source="WinEventLog:Microsoft-Windows-Sysmon/Operational" EventCode=28
| table _time, host, EventCode, Message- Data source
- Splunk Sysmon event data
- Assumptions
- Index, source, and parsed field names vary by deployment. Apply the documented field conditions after validating local field extraction.
dataset = microsoft_windows_raw
| filter edr_event_id = 28- Data source
- Cortex XDR microsoft_windows_raw
- Assumptions
- Confirm Provider is Microsoft-Windows-Sysmon because event IDs are not globally unique. Inspect raw provider fields because parsed names vary by collection path.
title: Sysmon Event ID 28
status: experimental
logsource:
product: windows
service: sysmon
detection:
selection:
EventID: 28
condition: selection
falsepositives:
- Legitimate administrative or system activity
level: informational- Data source
- Sigma Windows Sysmon log source
- Assumptions
- This rule retrieves the event and is not a standalone malicious-behavior detection. Add the event-specific conditions and correlations documented on this page.
Documented Values and Codes
| Field | Value | Meaning | Security relevance |
|---|---|---|---|
| EventID | 28 | Sysmon detected and blocked file shredding. | Interpret EventID with the other documented fields and correlated events; this value alone is not proof of compromise. Source |
| Image | SDelete | Sysinternals names SDelete as an example shredding tool, not the only possible source. | Interpret Image with the other documented fields and correlated events; this value alone is not proof of compromise. Source |
MITRE ATT&CK Mapping
- T1070.004Indicator Removal: File Deletion
Detection Notes
Alert when TargetFilename is under C:\Users\, C:\ProgramData\, C:\Windows\Temp, or AppData and Image resembles SDelete or an unapproved secure-delete binary. Microsoft documents Event 28 as blocked file shredding from tools such as SDelete; this supports T1070.004 File Deletion when an actor attempts to remove intrusion artifacts or evidence. Correlate ProcessGuid to Event 1 and retrieve related Event 23 archives or backups immediately.
Common False Positives
- Approved secure-delete tools may be used by administrators under documented data-handling procedures.
- Privacy tools and backup cleanup jobs can shred files during normal operations.
Related Events
Sample Log
UtcTime: 2026-07-13 03:07:00.000
Image: C:\Users\Public\sdelete.exe
TargetFilename: C:\Users\Public\loot.zip
Hashes: SHA256=REDACTED
ProcessGuid: {REDACTED}Frequently Asked Questions
What does Sysmon Event ID 28 mean?
Sysmon blocked an attempted file-shredding operation.
Does Event ID 28 always indicate malicious activity?
No. Approved secure-deletion workflows can invoke shredding tools.
How should Event ID 28 be investigated?
Review Image, TargetFilename, ProcessGuid, user context, and whether the deleted material relates to an investigation.
Sources
- 28: FileBlockShredding
Microsoft Sysinternals · vendor
- Indicator Removal: File Deletion (T1070.004)
MITRE ATT&CK · attack
- XDR Collector datasets
Palo Alto Networks · vendor
- Sigma Rules Specification
SigmaHQ · detection rule