Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 0bd55d614ee8d56f…

MALICIOUS

RTF / .DOC

3.8 KB
MD5: 860eea2deeaffb32f5fb2cfe65cdf9d5 SHA-1: c7808fb067dca3c9a6310c97e01168a24383dd70 SHA-256: 0bd55d614ee8d56fcc5688b5e7cc0245903bb774c1400d5b088482a7d7f3c1c2
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF document contains embedded OLE objects, specifically triggering the CVE-2017-11882 vulnerability related to the Equation Editor. This exploit allows for arbitrary code execution upon opening the document, likely as part of a spearphishing attachment campaign.

Heuristics 5

  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • Split hex Equation Editor ProgID + OLE object critical RTF_EQUATION_EDITOR
    RTF embeds the Equation.3 ProgID as hex bytes near OLE object activation and splits the byte stream with whitespace or an ignorable RTF group. This is an Equation Editor OLE activation surface commonly used by CVE-2017-11882 / CVE-2018-0802 exploit documents.
  • \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
  • 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_off0000008e.bin
537c2669eb6e800ef151672fceb9374d60c22c3eb5919edf1d613b61f0dec9c2
rtf-objdata-decoded RTF \objdata at offset 0x8E 1699 bytes