Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 26d8c29c78d860d5…

MALICIOUS

RTF / .DOC

24.2 KB First seen: 2022-08-16
MD5: 79c2433130bdd2a3ad54583fa1dcbdaa SHA-1: 884ae9c6d19cec69248f37cde3095d5baf58e70b SHA-256: 26d8c29c78d860d57bb5bbe1fb7eb23f57bc3f9a3d30eaa20f982cfea23a7f6b
160 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The sample is an RTF document containing embedded OLE objects, specifically triggering heuristics related to Equation Editor vulnerabilities (RTF_EQUATION_EDITOR) and OLE object activation ( RTF_OBJUPDATE, RTF_OLE10NATIVE_STREAM). This strongly suggests exploitation of a known vulnerability in the Equation Editor component to achieve arbitrary code execution. The embedded OLE object data likely contains a malicious payload designed to be downloaded and executed.

Heuristics 4

  • Ole10Native stream in RTF OLE object high CVE related RTF_OLE10NATIVE_STREAM
    RTF contains an embedded OLE object with an Ole10Native stream. This is a strong payload-container signal and is related to Word/OLE exploit delivery, but it is not specific enough on its own to assign a CVE.
  • Equation Editor CLSID critical RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • \objupdate forces OLE activation high RTF_OBJUPDATE
    RTF contains \objupdate — forces automatic OLE object instantiation when the document is opened, bypassing user interaction. Almost exclusively seen in Equation Editor exploit documents.
  • OLE object data medium RTF_OBJDATA
    RTF contains 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00001c52.bin
695b43321d5c3b57397c5d116d7d14dd42419e898219655f142ef541a1b0b556
rtf-objdata-decoded RTF \objdata at offset 0x1C52 4827 bytes