Xls.Downloader.Trojan-aa0b8f388d8573cd-aa0b8f388d8573cd-9950439-0 — Office (OOXML) / .XLSX malware analysis

Static analysis result for SHA-256 d020d147b7c1988c…

MALICIOUS

Office (OOXML) / .XLSX

727.0 KB Created: 2022-05-16 17:34:45 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2023-06-19
MD5: 2bb06693c9e1eaf5576f8a503495dcb9 SHA-1: e29c64134a68b3d58c18491f59c62428cf315930 SHA-256: d020d147b7c1988c868b9c84f738ce36f4e0d0271db8cc2b3e9d314acb0940f9
200 Risk Score

Malware Insights

Xls.Downloader.Trojan-aa0b8f388d8573cd-aa0b8f388d8573cd-9950439-0 · confidence 95%

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious File

The file is identified as a malicious Excel document by ClamAV, specifically 'Xls.Downloader.Trojan-aa0b8f388d8573cd-aa0b8f388d8573cd-9950439-0'. High-severity heuristics indicate the presence of an embedded OLE object, specifically an Equation Editor object, which carries a payload-like Ole10Native stream with an anomalous size. This strongly suggests the document is intended to exploit vulnerabilities within the Equation Editor or deliver a secondary malicious payload upon opening.

Heuristics 5

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/znS.jrg2E contains the Equation Editor CLSID, the legacy component exploited by CVE-2017-11882, CVE-2018-0802, and CVE-2018-0798.
  • ClamAV: Xls.Downloader.Trojan-aa0b8f388d8573cd-aa0b8f388d8573cd-9950439-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Trojan-aa0b8f388d8573cd-aa0b8f388d8573cd-9950439-0
  • NOP sled detected high SC_NOP_SLED
    Found 20+ consecutive 0x90 bytes
  • Equation Editor object carries payload-like Ole10Native stream high OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY
    Embedded OLE object declares the Equation Editor CLSID but stores a large high-entropy Ole10Native stream with malformed package sizing. This is an exploit-shaped Equation/OLE payload container seen in malicious OOXML samples. It is not assigned to a specific CVE unless the MTEF/Equation Native primitive also matches.
  • Embedded OLE object medium OOXML_OLE_OBJECT
    Document contains an embedded OLE object

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
ooxml_oleobject_00.bin
88a21a9fd2e27f99700d4590a74e5aedb01381447ea3ad335d1d21461b0972de		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/znS.jrg2E 839168 bytes
ooxml_oleobject_00_ole10native_00.bin
6987e4cc986c8fcd19244813c887a31d3d9e447347a1d7f0f1db972d34b76817		 ole-package OOXML xl/embeddings/znS.jrg2E Ole10Native stream: olE10nATiVe 830199 bytes
emf_00.emf
38f17a599ac5d645df3840bbb401710ef81573a747da20abbfc1b7d9a9273b58		 ooxml-emf OOXML EMF part: xl/media/image1.emf 169096 bytes

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