Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 0c7a731aa74b514e…

MALICIOUS

RTF / .DOC

18.7 KB
MD5: c35d368f1182d658e51507321cc072e1 SHA-1: fae56233348186a0d62967a32ddbdfebd028f4b5 SHA-256: 0c7a731aa74b514e0acc13470e017d477dfa2501e89a900d8a69b852e736455f
180 Risk Score

Malware Insights

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

The file is an RTF document containing embedded OLE object data, specifically triggering heuristics related to Equation Editor and CVE-2017-11882. This indicates the document is designed to exploit this vulnerability for client-side execution. The presence of ".objdata" and ".objupdate" sections further supports the exploitation of OLE object activation. No document body or script content was available for further analysis.

Heuristics 5

  • Obfuscated Equation Editor ProgID + activation critical CVE related RTF_EQUATION_EDITOR
    RTF decodes to an Equation.3 ProgID from top-level \objdata hex after nested RTF junk groups are ignored, and the document also contains \objemb plus \objupdate activation. This is an obfuscated Equation Editor exploit surface associated with CVE-2017-11882 / CVE-2018-0802 families, but no exact malformed MTEF CVE primitive was recovered from this object.
  • 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.
  • \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_off00001446.bin
9a4b50d388c431f664951790e2e4c6e7843c04f758fecdd3182d2ca8dc1cb1f1
rtf-objdata-decoded RTF \objdata at offset 0x1446 1584 bytes