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Windows Data Destruction Recursive Exec Files Deletion

Author
Teoderick Contreras, Splunk, Steven Dick
Source
upstream

The following analytic identifies a suspicious process that is recursively deleting executable files on a compromised host. It leverages Sysmon Event Codes 23 and 26 to detect this activity by monitoring for a high volume of deletions or overwrites of files with extensions like .exe, .sys, and .dll. This behavior is significant as it is commonly associated with destructive malware such as CaddyWiper, DoubleZero, and SwiftSlicer, which aim to make file recovery impossible. If confirmed malicious, this activity could lead to significant data loss and system instability, severely impacting business operations.

MITRE ATT&CK coverage

TacticTechniques
ImpactT1485 Data Destruction

Event coverage

ProviderEvent IDTitle
Sysmon23FileDelete (File Delete archived)
Sysmon26FileDeleteDetected (File Delete logged)

Stages and Predicates

Stage 1: search

search EventCode IN ("23", "26") TargetFilename IN ("*.dll", "*.exe", "*.sys")

Stage 2: search

search span="2m"

Stage 3: stats

stats BY action, dest, dvc, signature, signature_id, user, user_id, vendor_product

Stage 4: where

where count>=100

Stage 5: search

search

Stage 6: search

search

Stage 7: search

search `macro`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
EventCodein
  • "23" corpus 6 (splunk 6)
  • "26" corpus 6 (splunk 6)
TargetFilenamein
  • "*.dll" corpus 2 (splunk 2)
  • "*.exe" corpus 2 (splunk 2)
  • "*.sys"
countge
  • 100 corpus 2 (splunk 2)
spaneq
  • 2m

Neighbors

Often fire together

Rules that target events appearing in the same incident timelines. They pattern-match on adjacent steps of the same TTP, so an alert from one is often paired with alerts from these. Useful for triage context and for assembling chained-detection rules.

Share event IDs (chain-detection candidates)

Rules that observe the same Windows event-ID pairs as this one. If you're authoring a multi-stage / sequence rule that spans these events, these are the existing detections that already cover one or both endpoints.