Sigma rule: AWS EFS Fileshare Modified or Deleted

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-71e6d03d6878, updated 2022-10-09T00:00:00.000Z.

Rule

Title
AWS EFS Fileshare Modified or Deleted
Status
test
Level
medium
Author
Austin Songer @austinsonger
Date
2021-08-15
Modified
2022-10-09
File
rules/cloud/aws/cloudtrail/aws_efs_fileshare_modified_or_deleted.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects when a EFS Fileshare is modified or deleted.
You can't delete a file system that is in use.
If the file system has any mount targets, the adversary must first delete them, so deletion of a mount will occur before deletion of a fileshare.

Log source

product
aws
service
cloudtrail

Detection

selection:
    eventSource: elasticfilesystem.amazonaws.com
    eventName: DeleteFileSystem
condition: selection

False positives (as the rule lists them)

  • Unknown

Tags

  • attack.impact

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/cloud/aws/cloudtrail/aws_efs_fileshare_modified_or_deleted.yml

Sources and licences

  • SigmaHQ

    "AWS EFS Fileshare Modified or Deleted" by Austin Songer @austinsonger (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/cloud/aws/cloudtrail/aws_efs_fileshare_modified_or_deleted.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: AWS EFS Fileshare Modified or Deleted",
entity page, dataset version ref-71e6d03d6878, updated 2022-10-09T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/25cb1ba1-8a19-4a23-a198-d252664c8cef (accessed 2026-11-03).
Underlying source: SigmaHQ rule 25cb1ba1-8a19-4a23-a198-d252664c8cef, 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.