Potential Command and Control via Internet Explorer
editPotential Command and Control via Internet Explorer
editIdentifies instances of Internet Explorer (iexplore.exe) being started via the Component Object Model (COM) making unusual network connections. Adversaries could abuse Internet Explorer via COM to avoid suspicious processes making network connections and bypass host-based firewall restrictions.
Rule type: eql
Rule indices:
- logs-endpoint.events.library-*
- logs-endpoint.events.process-*
- logs-endpoint.events.network-*
Severity: medium
Risk score: 47
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References: None
Tags:
- Domain: Endpoint
- OS: Windows
- Use Case: Threat Detection
- Tactic: Command and Control
- Data Source: Elastic Defend
Version: 106
Rule authors:
- Elastic
Rule license: Elastic License v2
Rule query
editsequence by host.id, user.name with maxspan = 5s
[library where host.os.type == "windows" and dll.name : "IEProxy.dll" and process.name : ("rundll32.exe", "regsvr32.exe")]
[process where host.os.type == "windows" and event.type == "start" and process.parent.name : "iexplore.exe" and process.parent.args : "-Embedding"]
/* IE started via COM in normal conditions makes few connections, mainly to Microsoft and OCSP related domains, add FPs here */
[network where host.os.type == "windows" and network.protocol == "dns" and process.name : "iexplore.exe" and
not dns.question.name :
(
"*.microsoft.com",
"*.digicert.com",
"*.msocsp.com",
"*.windowsupdate.com",
"*.bing.com",
"*.identrust.com",
"*.sharepoint.com",
"*.office365.com",
"*.office.com"
)
] /* with runs=5 */
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Command and Control
- ID: TA0011
- Reference URL: https://attack.mitre.org/tactics/TA0011/
-
Technique:
- Name: Application Layer Protocol
- ID: T1071
- Reference URL: https://attack.mitre.org/techniques/T1071/
-
Tactic:
- Name: Execution
- ID: TA0002
- Reference URL: https://attack.mitre.org/tactics/TA0002/
-
Technique:
- Name: Inter-Process Communication
- ID: T1559
- Reference URL: https://attack.mitre.org/techniques/T1559/
-
Sub-technique:
- Name: Component Object Model
- ID: T1559.001
- Reference URL: https://attack.mitre.org/techniques/T1559/001/