Malicious Office (OOXML) / .XLSM — malware analysis report

Static analysis result for SHA-256 eb8645123e71d3b1…

MALICIOUS

Office (OOXML) / .XLSM

47.1 KB Created: 2020-02-01 18:28:07 UTC Authoring application: Microsoft Excel 12.0000
MD5: 01b802f0869703663ef19afed14abbd2 SHA-1: 8622ae99db506e794ee9f0bcf8d7bd7af7466930 SHA-256: eb8645123e71d3b1b95fc6fa0419168826c781367e05e642bc3093c60d8ed16a
320 Risk Score

Malware Insights

The critical heuristic CVE_2017_11882_EQUATION_NATIVE_CMD indicates the exploitation of CVE-2017-11882 through an embedded Equation Editor object. This exploit is designed to execute a command-line stager, as evidenced by the extracted command: 'cmd /c ren %tmp%\mm v&cSCRIpT %tmp%\v?..wsf ..C.......................................................'. The presence of an Auto_Open macro further suggests automatic execution upon opening the document, typical of malicious macro-enabled files.

Heuristics 8

  • CVE-2017-11882 — Equation Editor command stager critical CVE likely CVE_2017_11882_EQUATION_NATIVE_CMD
    Embedded Equation Editor OLE data contains an invalid Equation Native/MTEF stream with an embedded command stager. This is likely CVE-2017-11882 exploitation because the vulnerable Equation Editor component is reached and the malformed native stream directly carries process-launch bytes.
  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/oleObject3.bin contains the Equation Editor CLSID, the legacy component exploited by CVE-2017-11882, CVE-2018-0802, and CVE-2018-0798.
  • ClamAV: Xls.Malware.Generic-8176608-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Malware.Generic-8176608-0
  • Auto_Open macro high OLE_VBA_AUTO
    Auto_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • 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.
  • VBA project inside OOXML medium OOXML_VBA
    Document contains vbaProject.bin — VBA macros present
  • Embedded OLE object medium OOXML_OLE_OBJECT
    Document contains an embedded OLE object

Extracted artifacts 9

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
ab96d671b0f6645a0444fe98a6473465e0019a1f973753a33ee7dc074d6d8ae6
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 25040 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s). Carved macro source contains an auto-exec entry point and execution/download terms.
ooxml_oleobject_00.bin
aa7d5320383731b056c17aa344da4afaffb0d16dddc7496ef9550677e07c9b7d
ooxml-ole-object OOXML embedded OLE part: xl/embeddings/oleObject1.bin 3584 bytes
ooxml_oleobject_00_ole10native_00.bin
6530464814e5b1dce7c9fbfa3ac504ae72e8b8751b72a64be45fe1a5bd78ed57
ole-package OOXML xl/embeddings/oleObject1.bin Ole10Native stream: Ole10Native 1240 bytes
ooxml_oleobject_01.bin
aadbe44b59406c4ba0d2243d9450742341a20b5ace7dc7b2cc725110f76385cf
ooxml-ole-object OOXML embedded OLE part: xl/embeddings/oleObject2.bin 12800 bytes
ooxml_oleobject_01_ole10native_00.bin
69d8be1e7d6a56ccf79e374d5b327811b05b9221171a531d600fc36b7d4b41d8
ole-package OOXML xl/embeddings/oleObject2.bin Ole10Native stream: Ole10Native 9802 bytes
ooxml_oleobject_02.bin
464959801baf4a495a984dfab3d2962d78f7134048272e31cd1697e25d88b8b7
ooxml-ole-object OOXML embedded OLE part: xl/embeddings/oleObject3.bin 5936 bytes
ooxml_oleobject_03.bin
9d2cb46137213aa2602514eebc2dc0c4776b04923f2a58dd74d6560a3179e628
ooxml-ole-object OOXML embedded OLE part: xl/vbaProject.bin 44032 bytes
emf_00.emf
979dde2aed02f077c16ae53546c6df9eed40e8386d6db6fc36aee9f966d2cb82
ooxml-emf OOXML EMF part: xl/media/image1.emf 4968 bytes
emf_01.emf
4d4d1e7b04c99dcb8e885915068ad6f74cc2333e91580cdae5ccaa00c427247f
ooxml-emf OOXML EMF part: xl/media/image2.emf 1536 bytes