Malicious RTF — malware analysis report

Static analysis result for SHA-256 cc7761784dcb6709…

MALICIOUS

RTF

1.13 MB Created: 2020-01-21 10:50:00 First seen: 2020-05-25
MD5: 4a796207ffcdb7f78c33c3b36a15af90 SHA-1: ecff69d15076772ea8edec82c65420fd1429029d SHA-256: cc7761784dcb6709d08bc8ec78f0d97817a8d3c35869c29ff83bb0b70c7a021f
124 Risk Score

Malware Insights

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

The RTF file contains multiple OLE objects with large amounts of hex-encoded data, indicating an attempt to hide a payload. The presence of \objupdate suggests that the embedded OLE object is designed to be activated, likely leading to the execution of malicious code. The document body itself is a form for confirming attendance to a course, which could be used as a lure for spearphishing.

Heuristics 6

  • \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.
  • Large hex data blocks in OLE object high RTF_EXCESSIVE_HEX
    RTF contains ~1075KB of hex-encoded data inside \objdata sections — may hide a payload
  • OLE object data medium RTF_OBJDATA
    RTF contains 3 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://schemas.microsoft.com/office/word/2003/wordml In RTF body

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000e5953.bin rtf-objdata-decoded RTF \objdata at offset 0xE5953 114928 bytes
SHA-256: 7affb78d7a666df851ef1061c9c51a2743cc9709934d0c97ef485292b0939000
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.
objdata_01_off0011db59.bin rtf-objdata-decoded RTF \objdata at offset 0x11DB59 6847 bytes
SHA-256: e41db3b920b97d35fee7cad90d8e442e95f33a22b8414d5819876e58889c49d7
objdata_02_off0011db73.bin rtf-objdata-decoded RTF \objdata at offset 0x11DB73 6843 bytes
SHA-256: cbf708629437999ba26cf021c20424245fb880bd6c399adc3aa83dd2b149b130

Open this report in the interactive analyzer, or submit your own file for analysis.