RPC Firewall Alerts for SASec Scheduled Task Discovery (SASec)

Identifies RPC Firewall alerts for SASec interface calls related to scheduled task discovery.

FreeReviewedSigma · High · v5
Product
rpc_firewall
Category
application
Author
Sagie Dulce, Dekel Paz (SigmaHQ), DRL 1.1
Published
2022-01-01
Updated
2026-07-31
title: RPC Firewall Alerts for SASec Scheduled Task Discovery (SASec)
id: 6193be6b-e775-4fef-b938-b24695d6b2e3
status: test
description: This rule flags RPC Firewall EventLog entries indicating remote SASec interface calls that request scheduled task information. Attackers may use these RPC calls to enumerate scheduled tasks for discovery and follow-on actions. The detection relies on RPC Firewall telemetry with EventID 3 and a specific SASec InterfaceUuid, excluding operation numbers 0 and 1 from the matches.
references:
  - https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-tsch/d1058a28-7e02-4948-8b8d-4a347fa64931
  - https://github.com/jsecurity101/MSRPC-to-ATTACK/blob/ddd4608fe8684fcf2fcf9b48c5f0b3c28097f8a3/documents/MS-TSCH.md
  - https://github.com/zeronetworks/rpcfirewall
  - https://zeronetworks.com/blog/stopping-lateral-movement-via-the-rpc-firewall/
  - https://github.com/SigmaHQ/sigma/blob/master/rules/application/rpc_firewall/rpc_firewall_sasec_recon.yml
author: Sagie Dulce, Dekel Paz, Huntrule Team
date: 2022-01-01
tags:
  - attack.discovery
logsource:
  product: rpc_firewall
  category: application
  definition: 'Requirements: install and apply the RPC Firewall to all processes with "audit:true action:block uuid:378e52b0-c0a9-11cf-822d-00aa0051e40f"'
detection:
  selection:
    EventLog: RPCFW
    EventID: 3
    InterfaceUuid: 378e52b0-c0a9-11cf-822d-00aa0051e40f
  filter:
    OpNum:
      - 0
      - 1
  condition: selection and not filter
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: 0a3ff354-93fc-4273-8a03-1078782de5b7
    type: derived