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

Static analysis result for SHA-256 eb611f151f79cd5b…

MALICIOUS

Office (OLE) / .XLSX

1.21 MB
MD5: ccf7df23ad1496d6a4115fd8cd91aa40 SHA-1: 80ffc570465a3179d0f5b6ed5e556cc3c359d6af SHA-256: eb611f151f79cd5bdf64bfe15c4d4e64caaf7e9958a8a42e481e34e8d88dc171
140 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The sample is an encrypted OOXML file that utilizes a default password, a common technique for obfuscating malicious content. It contains an embedded Equation Editor OLE object, which is frequently used to deliver exploits. The anomaly in the Ole10Native stream within the Equation Editor object suggests it's designed to carry a payload, likely exploiting a vulnerability within the Equation Editor itself.

Heuristics 4

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Default-encrypted OOXML embedded OLE object xl/embeddings/oleObject1.bin contains the Equation Editor CLSID, the legacy component exploited by CVE-2017-11882, CVE-2018-0802, and CVE-2018-0798.
  • Default-encrypted OOXML exploit carrier layout high OOXML_ENCRYPTED_EXPLOIT_CARRIER_SHAPE
    Default-password encrypted OOXML package contains embedded OLE object parts and additional activation/decoy parts. This layout is common in malicious Excel exploit delivery and requires inspecting the decrypted package.
  • Equation Editor object carries payload-like Ole10Native stream high OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY
    Default-encrypted OOXML embedded OLE object declares the Equation Editor CLSID but stores a large high-entropy Ole10Native stream with malformed package sizing. This is exploit-shaped Equation/OLE payload evidence.
  • Office OOXML encrypted with default VelvetSweatshop password medium OFFICE_DEFAULT_PASSWORD_ENCRYPTED_OOXML
    OLE EncryptedPackage decrypts with Excel's built-in VelvetSweatshop password. Office opens this transparently, and malware uses it to hide OOXML exploit parts from scanners that only inspect the outer OLE container.