Jrat Office (OLE) / .DOCX malware analysis — malicious · 3f9d3925f753bb61

MALICIOUS

Office (OLE) / .DOCX

1.30 MB Created: 2021-06-23 12:48:00 Authoring application: Microsoft Office Word

MD5: ef027cdc43f1af9a9d017d5a3b1fb4e0 SHA-1: 8e2f40f8707dc90163b81f46ecc1eced0d7f4f66 SHA-256: 3f9d3925f753bb61c894317e1d84452fdaf135caa6431b8d41f5f6e5cc3f25b3

662 Risk Score

Malware Insights

Jrat · confidence 90%

MITRE ATT&CK

T1566.001 Phishing: Spearphishing Attachment T1204.002 User Execution: Malicious File T1059.005 Command and Scripting Interpreter: Visual Basic for Applications T1027 Obfuscated Files or Information T1547.001 Client Execution Application Registry Run Registry Key/ Startup Folder T1105 Ingress Tool Transfer

The sample is a malicious Word document containing a VBA macro that attempts to execute a dropped DLL named 'kikus.dll' using ShellExecuteA. The ClamAV detection 'Doc.Downloader.Jrat' directly supports the attribution to the Jrat family. The presence of an embedded PE executable and an Ole10Native package containing a DLL further confirms the payload delivery mechanism.

Heuristics 17

Office EPRINT stream contains EMF object high CVE related OLE_EPRINT_EMF_OBJECT

OLE ObjectPool contains an EPRINT stream with EMF data. This is rare in normal documents and is CVE-2007-3893/MS07-046-family evidence when paired with Office exploit payload anomalies, but the malformed EMF record is not proven by this rule alone.
OLE with Ole10Native — possible CVE-2026-21514 exploitation high CVE likely CVE_2026_21514

Document contains a Word OLE object with Ole10Native plus executable, PE, or risky remote-link indicators. CVE-2026-21514 exploits OLE metadata validation; this stronger structure is treated as likely exploitation.
Embedded PE executable critical OLE_EMBEDDED_EXE

MZ/PE header found inside document — possible embedded executable
ClamAV: Doc.Downloader.Jrat-6336393-1 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Doc.Downloader.Jrat-6336393-1
ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV

ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
Reference to WinExec API high SC_STR_WINEXEC

Reference to WinExec API
Reference to ShellExecute API high SC_STR_SHELLEXEC

Reference to ShellExecute API
Reference to LoadLibrary API high SC_STR_LOADLIBRARY

Reference to LoadLibrary API
Reference to GetProcAddress API high SC_STR_GETPROCADDRESS

Reference to GetProcAddress API
Document_Open macro high OLE_VBA_DOCOPEN

Document_Open macro
CreateObject call high OLE_VBA_CREATEOBJ

CreateObject call
Ole10Native package carries executable/script file type high OFFICE_PACKAGE_RISKY_FILE

OLE Package displayName or fullPath ends in an executable or script-capable extension. Even without UI extension spoofing, embedding a runnable payload inside an Office document is a high-risk delivery pattern.
VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC

Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
Suspicious extracted artifact high EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
Reference to VirtualAlloc API medium SC_STR_VIRTUALALLOC

Reference to VirtualAlloc API
VBA macros detected medium OLE_VBA_MACROS

Document contains VBA macro code
Embedded URL info EMBEDDED_URL

One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.

URL http://schemas.openxmlformats.org/drawingml/2006/main

Extracted artifacts 3

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`macros.bas` `b63fa2303f27e014e38c8c1471933c1dbb661e0d8d57af7ef2b73e4c07a34a03`	vba-macro	oletools.olevba.extract_macros (decoded VBA source)	2719 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 1 shell/COM execution token(s). Carved macro source contains an auto-exec entry point and execution/download terms.
`embedded_office_0008fa71.exe` `05d341c8dca72f829fb0795f40869abf90844696fa317998a9115f53b1729d3b`	embedded-pe	Office MZ+PE at offset 0x8FA71	777615 bytes
Detection ClamAV: Win.Packed.Midie-10008727-0 Obfuscation or payload: likely Carved macro source contains an auto-exec entry point and execution/download terms.
`ole10native_00.bin` `cb642180d5ca0e1764684883f7d277e3968657444d00fdb988a96062a674fe48`	ole-package	OLE Ole10Native stream: ObjectPool/_1685932448/Ole10Native	738613 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.