Potential CVE-2025-33053 Exploitation

  1[metadata]
  2creation_date = "2025/06/11"
  3integration = ["endpoint", "windows", "m365_defender", "sentinel_one_cloud_funnel"]
  4maturity = "production"
  5updated_date = "2025/06/11"
  6
  7[rule]
  8author = ["Elastic"]
  9description = """
 10Identifies a suspicious Diagnostics Utility for Internet Explorer child process. This may indicate the successful exploitation of the vulnerability CVE-2025-33053.
 11"""
 12from = "now-9m"
 13index = [
 14    "logs-endpoint.events.process-*",
 15    "winlogbeat-*",
 16    "logs-windows.sysmon_operational-*",
 17    "endgame-*",
 18    "logs-m365_defender.event-*",
 19    "logs-sentinel_one_cloud_funnel.*",
 20]
 21language = "eql"
 22license = "Elastic License v2"
 23name = "Potential CVE-2025-33053 Exploitation"
 24note = """## Triage and analysis
 25
 26### Investigating Potential CVE-2025-33053 Exploitation
 27
 28### Possible investigation steps
 29
 30- Review the process details to confirm the suspicious child process was indeed started by iediagcmd.exe.
 31- Check any URL file type creation before the alert and review the source of those files.
 32- Investigate the process tree and make sure all descendant processes are terminated.
 33- Examine the network activity associated with the suspicious process to detect any unauthorized data exfiltration or communication with known malicious IP addresses.
 34- Assess the system for any additional indicators of compromise, such as unexpected changes in system files or registry keys, which might suggest a broader attack.
 35
 36### False positive analysis
 37
 38- This behavior is very rare and should be highly suspicious.
 39
 40### Response and remediation
 41
 42- Isolate the affected system from the network to prevent further spread of the potential threat and to contain any malicious activity.
 43- Terminate the suspicious child process identified in the alert.
 44- Conduct a thorough scan of the affected system using updated antivirus or endpoint detection and response (EDR) tools to identify and remove any additional malicious files or processes.
 45- Escalate the incident to the security operations center (SOC) or incident response team for further investigation and to determine if the threat is part of a larger attack campaign.
 46- Implement additional monitoring and alerting for similar suspicious activities involving explorer.exe to enhance detection capabilities and prevent recurrence.
 47- Review and update endpoint security policies to restrict the execution of potentially malicious URL files."""
 48references = [
 49     "https://research.checkpoint.com/2025/stealth-falcon-zero-day/", 
 50     "https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-33053",
 51]
 52risk_score = 73
 53rule_id = "5e23495f-09e2-4484-8235-bdb150d698c9"
 54severity = "high"
 55tags = [
 56    "Domain: Endpoint",
 57    "OS: Windows",
 58    "Use Case: Threat Detection",
 59    "Tactic: Initial Access",
 60    "Tactic: Defense Evasion",
 61    "Data Source: Elastic Endgame",
 62    "Data Source: Elastic Defend",
 63    "Data Source: Sysmon",
 64    "Data Source: Microsoft Defender for Endpoint",
 65    "Data Source: SentinelOne",
 66    "Resources: Investigation Guide",
 67]
 68timestamp_override = "event.ingested"
 69type = "eql"
 70
 71query = '''
 72process where host.os.type == "windows" and event.type == "start" and
 73  process.parent.executable : "C:\\Program Files\\Internet Explorer\\iediagcmd.exe" and
 74  process.name : ("route.exe", "netsh.exe", "ipconfig.exe", "dxdiag.exe", "conhost.exe", "makecab.exe") and
 75  process.executable != null and
 76  not process.executable : ("C:\\Windows\\System32\\route.exe",
 77                            "C:\\Windows\\System32\\netsh.exe",
 78                            "C:\\Windows\\System32\\ipconfig.exe",
 79                            "C:\\Windows\\System32\\dxdiag.exe",
 80                            "C:\\Windows\\System32\\conhost.exe",
 81                            "C:\\Windows\\System32\\makecab.exe")
 82'''
 83
 84
 85[[rule.threat]]
 86framework = "MITRE ATT&CK"
 87[[rule.threat.technique]]
 88id = "T1566"
 89name = "Phishing"
 90reference = "https://attack.mitre.org/techniques/T1566/"
 91[[rule.threat.technique.subtechnique]]
 92id = "T1566.001"
 93name = "Spearphishing Attachment"
 94reference = "https://attack.mitre.org/techniques/T1566/001/"
 95
 96[[rule.threat.technique.subtechnique]]
 97id = "T1566.002"
 98name = "Spearphishing Link"
 99reference = "https://attack.mitre.org/techniques/T1566/002/"
100
101[rule.threat.tactic]
102id = "TA0001"
103name = "Initial Access"
104reference = "https://attack.mitre.org/tactics/TA0001/"
105
106
107
108
109[[rule.threat]]
110framework = "MITRE ATT&CK"
111[[rule.threat.technique]]
112id = "T1218"
113name = "System Binary Proxy Execution"
114reference = "https://attack.mitre.org/techniques/T1218/"
115
116
117[rule.threat.tactic]
118id = "TA0005"
119name = "Defense Evasion"
120reference = "https://attack.mitre.org/tactics/TA0005/"