Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 837f4731485ca64a…

MALICIOUS

RTF / .DOC

136.3 KB
MD5: acb320957462d82c9c0e3a612d66c09f SHA-1: 0a51116e243e140f8296ccdd4ebc330178b85f75 SHA-256: 837f4731485ca64ad7dfce9c2117085c620cb8025ca5f0e7eb4fc38a6861701f
182 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object with data indicative of the Equation Editor vulnerability (CVE-2017-11882). The presence of \objdata and \objupdate directives strongly suggests an attempt to trigger this exploit upon opening the document. This exploit is known to download and execute arbitrary code, making it a common delivery mechanism for further malware.

Heuristics 5

  • 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
  • ClamAV: Rtf.Exploit.CVE_2017_11882-6584355-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2017_11882-6584355-1
  • \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
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000058.bin
ee756933e2b4a6a53b041a1787c39a4c29138c5a9f54b3bdef39228c0db5bf96
rtf-objdata-decoded RTF \objdata at offset 0x58 69700 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.91, consistent with packed or encrypted content.