Malicious RTF — malware analysis report

Static analysis result for SHA-256 c3d93fd4a248da7d…

MALICIOUS

RTF

25.0 KB First seen: 2023-05-06
MD5: b399ca1298c7cb77fe79901d11a28452 SHA-1: caa0421f8c96b4349873c6f8c2e2f5045f7d06ad SHA-256: c3d93fd4a248da7dbf8400da8b0efbd6a2f2aa549cf829dae9902ca9d4fec240
180 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object that leverages the Equation Editor vulnerability (CVE-2017-11882). This exploit is designed to execute arbitrary code, indicating the file's primary purpose is to compromise the system by delivering a secondary payload. No document body text was available for further analysis of the lure.

Heuristics 5

  • Equation Editor Ole10Native payload — CVE-2017-11882 likely critical CVE likely CVE_2017_11882_EQUATION_OLE10NATIVE
    RTF decodes to an activated Microsoft Equation 3.0 OLE storage whose payload is a high-entropy Ole10Native stream rather than normal Equation Native/MTEF data. This is a weaponized Equation Editor RCE delivery shape consistent with CVE-2017-11882/CVE-2018-0802.
  • 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.
  • \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 1 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000117e.bin
64441f259fd1dd11ca41e195c604654213d589cd49b693c72c48f70038528312
rtf-objdata-decoded RTF \objdata at offset 0x117E 4166 bytes