Detection rules › Splunk
Malicious Document Execution (Sysmon)
This rule is attempting to detect anytime a Microsoft Office OR Adobe program (ex. Word, Excel, Adobe) spawns a process that could be indicative of those Office programs used to deliver malicious code
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Initial Access | |
| Execution |
References
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
Rule body
id: '1050.1052'
title: Malicious Document Execution
description: 'This rule is attempting to detect anytime a Microsoft Office OR Adobe
program (ex. Word, Excel, Adobe) spawns a process that could be indicative of those
Office programs used to deliver malicious code. -- Threat Actor Association: Actinium/Gamaredon/Primitive
Bear, APT10/menuPass, APT29, APT34/OilRig, APT37, Arid Viper/APT C-23, Blind Eagle/APT-C-36,
Carbanak, Evilnum, FIN6, FIN7, Gamaredon Group/Shuckworm, Kimsuky, Lazarus, ModifiedElephant,
MuddyWater, NewsPenguin, RedEyes, RomCom, SideWinder, TA428, TA505, TA551, Turla
(akaSecret Blizzard, KRYPTON, and UAC-0003), Winter Vivern, WIRTE, Wizard Spider
-- Software Association: Bazarloder, Black Basta, Clop, Conti, Dridex, Emotet, GlowSand,
Hancitor, IcedID, Lockbit, MINEBRIDGE, MirrorBlast, PowerShortShell, QakBot, RATDispenser,
Sodinokibi/REvil, SquirrelWaffle, Trickbot, Zumkong -- #TrendingThreat #Russia #Ukraine'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_sysmon` EventCode=1 AND (TERM("powershell.exe")
OR TERM("cmd.exe") OR TERM("wscript.exe") OR TERM("cscript.exe") OR "regsvr32.exe"
OR "rundll32.exe" OR "wmic" OR "control.exe") AND ("Microsoft Office" OR "WINWORD.EXE"
OR "EXCEL.EXE" OR "POWERPNT.EXE" OR "ONENOTE.EXE" OR "MSACCESS.EXE" OR "OUTLOOK.EXE"
OR "VISIO.EXE" OR "WINPROJ.EXE" OR "AcroRd32.exe" OR "Acrobat.exe" OR "FoxitPhantomPDF.exe"
OR "FoxitReader.exe" OR "wordpad.exe" ) | table _time, host, user process, parent_*,
process_*, signature_id | bin span=1s | stats values(*) as * by _time, host | where
match(parent_process_path,"(?i)(Microsoft Office)|(WINWORD\.EXE)|(EXCEL\.EXE)|(POWERPNT\.EXE)|(ONENOTE\.EXE)|(MSACCESS\.EXE)|(OUTLOOK\.EXE)|(VISIO\.EXE)|(WINPROJ\.EXE)|(AcroRd32\.exe)|(Acrobat\.exe)|(FoxitPhantomPDF\.exe)|(FoxitReader\.exe)|(wordpad.exe)") '
techniques:
- initial-access:phishing:spearphishing attachment
- execution:user execution:malicious link
- execution:user execution:malicious file
technique_id:
- T1566.001
- T1204.001
- T1204.002
data_category:
- Windows Sysmon
references:
- https://success.trendmicro.com/solution/000279049
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_sysmon` EventCode=1 AND (TERM("powershell.exe") OR TERM("cmd.exe") OR TERM("wscript.exe") OR TERM("cscript.exe") OR "regsvr32.exe" OR "rundll32.exe" OR "wmic" OR "control.exe") AND ("Microsoft Office" OR "WINWORD.EXE" OR "EXCEL.EXE" OR "POWERPNT.EXE" OR "ONENOTE.EXE" OR "MSACCESS.EXE" OR "OUTLOOK.EXE" OR "VISIO.EXE" OR "WINPROJ.EXE" OR "AcroRd32.exe" OR "Acrobat.exe" OR "FoxitPhantomPDF.exe" OR "FoxitReader.exe" OR "wordpad.exe" )
Stage 2: table
| table _time, host, user process, parent_*, process_*, signature_id
Stage 3: bucket
| bin span=1s
Stage 4: stats
| stats values(*) as * by _time, host
Stage 5: where
| where match(parent_process_path,"(?i)(Microsoft Office)|(WINWORD\.EXE)|(EXCEL\.EXE)|(POWERPNT\.EXE)|(ONENOTE\.EXE)|(MSACCESS\.EXE)|(OUTLOOK\.EXE)|(VISIO\.EXE)|(WINPROJ\.EXE)|(AcroRd32\.exe)|(Acrobat\.exe)|(FoxitPhantomPDF\.exe)|(FoxitReader\.exe)|(wordpad.exe)")
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
EventCode | eq |
| field:"EventID" kind:eq value:"1" |
parent_process_path | regex_match |
| field:"parent_process_name" kind:regex_match |
Search terms
These SPL tokens match against raw event text.
| Stage | Term |
|---|---|
| 1 | "powershell.exe" |
| 1 | "cmd.exe" |
| 1 | "wscript.exe" |
| 1 | "cscript.exe" |
| 1 | "regsvr32.exe" |
| 1 | "rundll32.exe" |
| 1 | "wmic" |
| 1 | "control.exe" |
| 1 | "Microsoft Office" |
| 1 | "WINWORD.EXE" |
| 1 | "EXCEL.EXE" |
| 1 | "POWERPNT.EXE" |
| 1 | "ONENOTE.EXE" |
| 1 | "MSACCESS.EXE" |
| 1 | "OUTLOOK.EXE" |
| 1 | "VISIO.EXE" |
| 1 | "WINPROJ.EXE" |
| 1 | "AcroRd32.exe" |
| 1 | "Acrobat.exe" |
| 1 | "FoxitPhantomPDF.exe" |
| 1 | "FoxitReader.exe" |
| 1 | "wordpad.exe" |