Suspicious RDP ActiveX Client Loaded

 1[metadata]
 2creation_date = "2020/11/19"
 3integration = ["endpoint", "windows"]
 4maturity = "production"
 5updated_date = "2024/05/21"
 6
 7[rule]
 8author = ["Elastic"]
 9description = """
10Identifies suspicious Image Loading of the Remote Desktop Services ActiveX Client (mstscax), this may indicate the
11presence of RDP lateral movement capability.
12"""
13from = "now-9m"
14index = ["logs-endpoint.events.library-*", "winlogbeat-*", "logs-windows.sysmon_operational-*", "endgame-*"]
15language = "eql"
16license = "Elastic License v2"
17name = "Suspicious RDP ActiveX Client Loaded"
18references = ["https://posts.specterops.io/revisiting-remote-desktop-lateral-movement-8fb905cb46c3"]
19risk_score = 47
20rule_id = "71c5cb27-eca5-4151-bb47-64bc3f883270"
21setup = """## Setup
22
23If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2,
24events will not define `event.ingested` and default fallback for EQL rules was not added until version 8.2.
25Hence for this rule to work effectively, users will need to add a custom ingest pipeline to populate
26`event.ingested` to @timestamp.
27For more details on adding a custom ingest pipeline refer - https://www.elastic.co/guide/en/fleet/current/data-streams-pipeline-tutorial.html
28"""
29severity = "medium"
30tags = [
31    "Domain: Endpoint",
32    "OS: Windows",
33    "Use Case: Threat Detection",
34    "Tactic: Lateral Movement",
35    "Data Source: Elastic Endgame",
36    "Data Source: Elastic Defend",
37    "Data Source: Sysmon",
38]
39timestamp_override = "event.ingested"
40type = "eql"
41
42query = '''
43any where host.os.type == "windows" and
44 (event.category : ("library", "driver") or (event.category == "process" and event.action : "Image loaded*")) and
45 (?dll.name : "mstscax.dll" or file.name : "mstscax.dll") and
46   /* depending on noise in your env add here extra paths  */
47  process.executable : (
48    "C:\\Windows\\*",
49    "C:\\Users\\Public\\*",
50    "C:\\Users\\Default\\*",
51    "C:\\Intel\\*",
52    "C:\\PerfLogs\\*",
53    "C:\\ProgramData\\*",
54    "\\Device\\Mup\\*",
55    "\\\\*"
56  ) and
57  /* add here FPs */
58  not process.executable : (
59    "?:\\Windows\\System32\\mstsc.exe",
60    "?:\\Windows\\SysWOW64\\mstsc.exe",
61    "?:\\Windows\\System32\\vmconnect.exe",
62    "?:\\Windows\\System32\\WindowsSandboxClient.exe",
63    "?:\\Windows\\System32\\hvsirdpclient.exe"
64  )
65'''
66
67
68[[rule.threat]]
69framework = "MITRE ATT&CK"
70[[rule.threat.technique]]
71id = "T1021"
72name = "Remote Services"
73reference = "https://attack.mitre.org/techniques/T1021/"
74[[rule.threat.technique.subtechnique]]
75id = "T1021.001"
76name = "Remote Desktop Protocol"
77reference = "https://attack.mitre.org/techniques/T1021/001/"
78
79
80
81[rule.threat.tactic]
82id = "TA0008"
83name = "Lateral Movement"
84reference = "https://attack.mitre.org/tactics/TA0008/"