sigma-rules/rules/windows/execution_suspicious_short_program_name.toml

[metadata]
creation_date = "2020/11/15"
maturity = "production"
updated_date = "2022/03/31"

[rule]
author = ["Elastic"]
description = """
Identifies process execution with a single character process name. This is often done by adversaries while staging or
executing temporary utilities.
"""
from = "now-9m"
index = ["winlogbeat-*", "logs-endpoint.events.*", "logs-windows.*"]
language = "eql"
license = "Elastic License v2"
name = "Suspicious Execution - Short Program Name"
note = """## Config

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.
"""
risk_score = 47
rule_id = "17c7f6a5-5bc9-4e1f-92bf-13632d24384d"
severity = "medium"
tags = ["Elastic", "Host", "Windows", "Threat Detection", "Execution"]
timestamp_override = "event.ingested"
type = "eql"

query = '''
process where event.type in ("start", "process_started") and length(process.name) > 0 and
 length(process.name) == 5 and host.os.name == "Windows" and length(process.pe.original_file_name) > 5
'''