Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 57a9b2bd9c9b9cef…

MALICIOUS

RTF / .DOC

8.3 KB
MD5: 9855c3ec4166c3edbdbff8df1002e4eb SHA-1: 2f5eac13d134c288f2f4cb2cf126e12232c2514d SHA-256: 57a9b2bd9c9b9cef07dae59700c8a2f98b1a1c36a5b389709b1b296211de70ef
200 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.003 Windows Command Shell

The RTF file contains an embedded OLE object with a CLSID indicative of the Equation Editor. Heuristics confirm the presence of an OLE object and the use of \objupdate, strongly suggesting exploitation of CVE-2017-11882. This vulnerability allows for arbitrary code execution when the object is activated, likely leading to the download and execution of a second-stage payload. The SHA256 hash is included as an IOC.

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
  • 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_off0000006a.bin
da1b46cee5811a2e80cdeb558e54e5161e140c07b566787267943e33f6220cd5
rtf-objdata-decoded RTF \objdata at offset 0x6A 4147 bytes