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

Static analysis result for SHA-256 b60dccaf97a4cb2e…

MALICIOUS

Office (OLE) / .XLS

1.37 MB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel First seen: 2023-07-17
MD5: 43d1618f48b3d7d8f52d163253a3f3c9 SHA-1: 309684e1dc8d3647bf654ee1d71ad3fa60fd83fa SHA-256: b60dccaf97a4cb2e8dbbc565f20982e6c778878b35587d28eb47585cdc0b41a0
392 Risk Score

Malware Insights

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

The file is an Excel spreadsheet containing an embedded Equation Editor object that exploits CVE-2017-11882. This object contains a secondary PDF payload which, in turn, has a direct link to an executable payload. The ClamAV detection signature 'Xls.Downloader.94c25b356b5a6cac-9978798-0' further confirms its malicious nature as a downloader. The embedded PDF also exhibits suspicious static findings and parser evasion techniques.

Heuristics 10

  • 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.
  • PDF link points directly to executable/archive payload critical PDF_DIRECT_PAYLOAD_LINK
    PDF contains a clickable HTTP(S) URI whose path ends in an executable, script, shortcut, disk image, or archive extension. Documents can legitimately link to installers, so this is a high-risk delivery indicator rather than a standalone exploit fingerprint.
  • 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.
  • Clickable PDF combines external action with parser-evasion structure high PDF_ACTION_PARSER_EVASION
    PDF has an external clickable URI together with object graph or xref structures that make parsers disagree, such as divergent duplicate objects, parser divergence, or xref offset mismatch. That combination is stronger than a plain link: the document is both an outward-action carrier and a parser-confusion/evasion sample.
  • 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.
  • 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 https://https://www.google.co.in/example.com
    • 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/

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
7f5606d11f1a6fea121f511a87633178d1cd8a6e4bb88693f4dc6e82bff6b563
ole-package OLE Ole10Native stream: MBD001CC246/olE10nATIVE 1388 bytes
font_00_sfnt_off00007f7d.bin
68d167e68895a344f3603a4efd0d8438eb8fdebe759cee48f2b4adf75c76c961
pdf-font-stream PDF embedded font (sfnt) at offset 0x7F7D 12100 bytes
font_01_sfnt_off00009d95.bin
50551000b9f90b3f445ee94749557d9ddf96697a74984b3ccf3d2bae66910750
pdf-font-stream PDF embedded font (sfnt) at offset 0x9D95 15820 bytes
polyglot_child_pdf_off00001200.pdf
82a293f1cd3654f2a4403390748faec2c288e1e9050a810cd4d1c91b8201e5e8
polyglot-child-pdf Secondary PDF body inside ole container at offset 0x1200 1432064 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off00006200.pdf
4ffec6cbace475c3b8afeb637873b0a730382558a4c225a76a364b2d40f70108
polyglot-child-pdf Secondary PDF body inside ole container at offset 0x6200 1411584 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off0000e600.pdf
d0c02255193566ebb33d618412699e2171eacd1c22132fb2efb5bcc1443c969d
polyglot-child-pdf Secondary PDF body inside ole container at offset 0xE600 1377792 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off00023e00.pdf
67914f046226f70c66e32fb83cdf4543e13b7c3b2cf59e1fd2c357b850fed19d
polyglot-child-pdf Secondary PDF body inside ole container at offset 0x23E00 1289728 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely