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

Static analysis result for SHA-256 4278b4a6e4121dcb…

MALICIOUS

Office (OLE) / .XLSX

78.0 KB First seen: 2022-06-22
MD5: 507fe49694225118f2d10152917585c5 SHA-1: 5661976623dee10aa38bd7b007cb84bc31e01efd SHA-256: 4278b4a6e4121dcb49241648506a1b5aaf2ab6f7e3d06d1a8321808bfd21005b
160 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1566 Phishing T1059 Command and Scripting Interpreter

The sample is an encrypted Office document, indicated by the 'OFFICE_ENCRYPTED_PACKAGE' and 'OFFICE_DEFAULT_PASSWORD_ENCRYPTED_OOXML' heuristics. The 'OOXML_ENCRYPTED_EXPLOIT_CARRIER_SHAPE' and 'OLE_EQUATION_EDITOR' heuristics point to the exploitation of a vulnerability within the Equation Editor OLE object, specifically identified as 'CVE_2018_0798_EQUATION_NATIVE_ANOMALY'. This suggests the document is designed to deliver a payload by exploiting this known vulnerability.

Heuristics 5

  • 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.
  • CVE-2018-0798 — anomalous Equation Editor native stream high CVE likely CVE_2018_0798_EQUATION_NATIVE_ANOMALY
    Default-encrypted OOXML contains embedded Equation Editor data with anomalous native stream bytes consistent with a CVE-2018-0798-style exploit. This is treated as likely CVE evidence because the Equation object is malformed and payload-like.
  • 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.
  • Office document is password-encrypted medium OFFICE_ENCRYPTED_PACKAGE
    OLE container holds MS-OFFCRYPTO encrypted package (Standard Encryption (Office 2007, AES)).
  • 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.

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