Cisco Secure Firewall - Malware File Downloaded

name: Cisco Secure Firewall - Malware File Downloaded
id: 3cc93f52-5aa6-4b7f-83b9-3430b1436813
version: 8
creation_date: '2025-04-09'
modification_date: '2026-05-13'
author: Nasreddine Bencherchali, Splunk
status: production
type: Anomaly
description: |
    The following analytic detects file downloads that were classified as malware by Cisco Secure Firewall Threat Defense. It relies on the `SHA_Disposition` field with a value of "Malware" and includes metadata such as file name, file_hash hash, and threat classification. This analytic is critical for surfacing file-based threats that are identified via Cisco's AMP or Threat Grid integrations. If confirmed malicious, this could indicate delivery of malware.
data_source:
    - Cisco Secure Firewall Threat Defense File Event
search: |
    `cisco_secure_firewall` EventType=FileEvent SHA_Disposition="Malware" FileDirection="Download"
    | lookup cisco_secure_firewall_filetype_lookup Name as FileType OUTPUT Description
    | stats count min(_time) as firstTime max(_time) as lastTime
            values(uri) as uri
            values(ClientApplication) as ClientApplication
            values(file_hash) as file_hash
            by FileDirection dest src dest_port FileType app file_name ThreatName Description
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | table firstTime lastTime src dest dest_port FileDirection FileType Description uri file_name file_hash app ClientApplication ThreatName SHA_Disposition
    | `cisco_secure_firewall___malware_file_downloaded_filter`
how_to_implement: |
    This search requires Cisco Secure Firewall Threat Defense Logs, which
    includes the FileEvent EventType. This search uses an input macro named `cisco_secure_firewall`.
    We strongly recommend that you specify your environment-specific configurations
    (index, source, sourcetype, etc.) for Cisco Secure Firewall Threat Defense logs. Replace the macro definition
    with configurations for your Splunk environment. The search also uses a post-filter
    macro designed to filter out known false positives.
    The logs are to be ingested using the Splunk Add-on for Cisco Security Cloud (https://splunkbase.splunk.com/app/7404).
    The malware & file access policy must also enable logging.
known_false_positives: Malicious verdicts could be outdated or incorrect due to retroactive threat intel.
references:
    - https://www.cisco.com/c/en/us/td/docs/security/firepower/741/api/FQE/secure_firewall_estreamer_fqe_guide_740.pdf
intermediate_findings:
    entities:
        - field: src
          type: system
          score: 20
          message: File with Malware disposition downloaded from $dest$ over port $dest_port$ by $src$
threat_objects:
    - field: file_hash
      type: file_hash
    - field: file_name
      type: file_name
analytic_story:
    - Cisco Secure Firewall Threat Defense Analytics
asset_type: Endpoint
mitre_attack_id:
    - T1203
    - T1105
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: network
security_domain: endpoint