Files
splunk-security_content/detections/batch_file_write_to_system32.yml
2020-05-06 17:42:38 +02:00

39 lines
1.7 KiB
YAML

name: Batch File Write to System32
id: 503d17cb-9eab-4cf8-a20e-01d5c6987ae3
version: 1
date: '2018-12-14'
description: The search looks for a batch file (.bat) written to the Windows system
directory tree.
how_to_implement: You must be ingesting data that records the file-system activity
from your hosts to populate the Endpoint file-system data-model node. If you are
using Sysmon, you will need a Splunk Universal Forwarder on each endpoint from which
you want to collect data.
type: ESCU
references: []
author: Rico Valdez, Splunk
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
as lastTime values(Filesystem.dest) as dest values(Filesystem.file_name) as file_name
values(Filesystem.user) as user from datamodel=Endpoint.Filesystem by Filesystem.file_path
| `drop_dm_object_name(Filesystem)` | `security_content_ctime(lastTime)` | `security_content_ctime(firstTime)`|
rex field=file_name "(?<file_extension>\.[^\.]+)$" | search file_path=*system32*
AND file_extension=.bat | `batch_file_write_to_system32_filter`'
known_false_positives: It is possible for this search to generate a notable event
for a batch file write to a path that includes the string "system32", but is not
the actual Windows system directory. As such, you should confirm the path of the
batch file identified by the search. In addition, a false positive may be generated
by an administrator copying a legitimate batch file in this directory tree. You
should confirm that the activity is legitimate and modify the search to add exclusions,
as necessary.
tags:
analytics_story:
- SamSam Ransomware
kill_chain_phases:
- Delivery
cis20:
- CIS 8
nist:
- PR.PT
- DE.CM
security_domain: endpoint
asset_type: Endpoint