Malicious Office (OLE) / .XLS — malware analysis report

Static analysis result for SHA-256 023587dfb8efcb39…

MALICIOUS

Office (OLE) / .XLS

3.04 MB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel First seen: 2023-06-16
MD5: 47bbcc7603e9979b6dd4e9b4a50042f3 SHA-1: ad926408828c4798c897a3eb2ac993be28fd28ea SHA-256: 023587dfb8efcb39cb353a413c2773cfded347e5d8aec8086ececf395725237a
294 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.001 Malicious Link: Malicious Link T1566 Phishing T1566.002 Phishing: Spearphishing Attachment T1059.005 Command and Scripting Interpreter: Visual Basic

The file is an Excel spreadsheet containing an embedded Equation Editor object that exploits CVE-2017-11882. This object contains a payload that, when triggered, leads to the execution of a secondary embedded PDF file. The PDF itself exhibits suspicious static findings and contains URIs, suggesting it is part of a multi-stage attack. The ClamAV detection as 'Xls.Downloader' further supports its malicious nature.

Heuristics 9

  • Equation Editor Ole10Native payload — CVE-2017-11882 critical CVE likely CVE_2017_11882_EQUATION_OLE10NATIVE
    An embedded Microsoft Equation 3.0 object (CLSID 0002CE02-0000-0000-C000-000000000046) carries an Ole10Native packager stream instead of the normal Equation Native/MTEF data. This is the weaponized Equation Editor RCE delivery shape used by CVE-2017-11882 / CVE-2018-0802 maldocs. The payload (font-record overflow + shellcode) is frequently encrypted and the stream name case-scrambled to evade scanners, but an Equation object holding an Ole10Native stream has no benign use.
  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Contains Equation Editor object — related to CVE-2017-11882 / CVE-2018-0802 exploitation, but CLSID presence alone is not the malformed MTEF exploit primitive.
  • Secondary embedded PDF body has suspicious static findings critical POLYGLOT_CHILD_PDF_STATIC_TRIAGE
    A valid PDF body was found at a nonzero offset inside another container and its carved contents matched PDF exploit or lure heuristics. This catches polyglots where the top-level magic routes to ZIP/OLE while a PDF reader or downstream parser opens the hidden PDF payload.
  • ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.94c25b356b5a6cac-9978798-0
  • 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.
  • VBA project contains no executable statements low OLE_VBA_MACROS
    Document contains a VBA project, but extracted modules only contain attributes/options/comments and no executable statements.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/pdf/1.3/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/mm/
    • https://www.business.hsbc.com.hk/en-gb/resource-centre/commercial-tariffs
    • https://www.online-banking.business.hsbc.com.hk/portalserver/hsbc/dbbpage/commercial/online/timetable/cutoff

Extracted artifacts 8

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
7f506327609c082af1cd37dde23bc2c71a000f7d1ef530b6abb66775040a7673		 vba-macro oletools.olevba.extract_macros (decoded VBA source) 1206 bytes
ole10native_00.bin
8b54d7ee82d39b558afaa374955e0565d9dfa31ed4be59fd60c811a963d898af		 ole-package OLE Ole10Native stream: MBD0143AC01/OLE10natIvE 1389 bytes
font_00_sfnt_off0001cf26.bin
9a85db95c587691a5874b31b664b687edfec6192fc00b1fd6cbfbbe56ee0e2a8		 pdf-font-stream PDF embedded font (sfnt) at offset 0x1CF26 13936 bytes
font_01_sfnt_off0001f5a1.bin
3c119924dbdaf638dde5d0098e911912b53026a6636c8a487543986d08e96bb1		 pdf-font-stream PDF embedded font (sfnt) at offset 0x1F5A1 13556 bytes
polyglot_child_pdf_off00008400.pdf
b861dd6b49a76e1e4e1bb4fb3f14c82e83d4883ade91cd1d73d49c9054cb3420		 polyglot-child-pdf Secondary PDF body inside ole container at offset 0x8400 3156992 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off0001da00.pdf
a8b44f616ca285dcf5779c22d52f3e7610a1c41a191080337f8b79dc86a45592		 polyglot-child-pdf Secondary PDF body inside ole container at offset 0x1DA00 3069440 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off00088c00.pdf
8d4a5a927f51fa788347acef72fc5208c5e876b7f8b8d3d7dedafb46096a994f		 polyglot-child-pdf Secondary PDF body inside ole container at offset 0x88C00 2630656 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off0009e200.pdf
1f9b486ebda5d55b47984ac9aec99ad60f36c150cef2de58616aa8726a001055		 polyglot-child-pdf Secondary PDF body inside ole container at offset 0x9E200 2543104 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely

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