Xls.Downloader.94c25b356b5a6cac-9978798-0 — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 ebd76ed616fef2f1…

MALICIOUS

Office (OLE) / .XLS

1.37 MB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel First seen: 2023-07-14
MD5: 3aaea611bbf04af88f795927bca16b9d SHA-1: 74084df258e08f86c5c8d62abc51b14649fd8660 SHA-256: ebd76ed616fef2f1a27deb6f252ffe2d62ab99bc90189d72e99f95fbf737200d
392 Risk Score

Malware Insights

Xls.Downloader.94c25b356b5a6cac-9978798-0 · confidence 95%

MITRE ATT&CK
T1204.002 User Execution: Malicious File T1566.001 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 secondary PDF payload that includes a direct link to an executable or archive. The ClamAV detection name 'Xls.Downloader.94c25b356b5a6cac-9978798-0' further supports its role as a downloader. No VBA macros were found to be executable, but the exploit chain is clear.

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
0af5753dab29ad4c54210451ff72a8d726b85aa921d13d173e3de518bf8dcf59
ole-package OLE Ole10Native stream: MBD0028FA42/oLE10nAtIve 1993 bytes
font_00_sfnt_off0001d97d.bin
68d167e68895a344f3603a4efd0d8438eb8fdebe759cee48f2b4adf75c76c961
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D97D 12100 bytes
font_01_sfnt_off0001f795.bin
50551000b9f90b3f445ee94749557d9ddf96697a74984b3ccf3d2bae66910750
pdf-font-stream PDF embedded font (sfnt) at offset 0x1F795 15820 bytes
polyglot_child_pdf_off00001200.pdf
25fe6967644f150cb97447b16a602a3bc3f30376af6d526ceb3005a4a1923fc0
polyglot-child-pdf Secondary PDF body inside ole container at offset 0x1200 1432576 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off00006400.pdf
c6179f4fbe7111febe603ca29f523bac65ec49a5d8420f531012a8fa71d0b49d
polyglot-child-pdf Secondary PDF body inside ole container at offset 0x6400 1411584 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off0001bc00.pdf
ba085aa69bc4bf289e22ff35fb06c732b9030f617e6a41241d90bb9078a1816b
polyglot-child-pdf Secondary PDF body inside ole container at offset 0x1BC00 1323520 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely
polyglot_child_pdf_off00023e00.pdf
c11181e9eff1c2ccc8a85e43e3173febcf3a56fbee1b402b22be6cbe701c2749
polyglot-child-pdf Secondary PDF body inside ole container at offset 0x23E00 1290240 bytes
Detection
ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0
Obfuscation or payload: unlikely