Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 4f6ccd818ef45e6e…

MALICIOUS

RTF / .DOC

8.5 KB
MD5: a757428f0d7285eb9010ef06a1c557bb SHA-1: 7e7e179086c808a7c1e956f7a35b083a02dfab51 SHA-256: 4f6ccd818ef45e6eb31b57e1331b3b2cf6fcd896a455f321a135421652892e1c
220 Risk Score

Malware Insights

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

The file is an RTF document containing an embedded OLE object that leverages the Equation Editor vulnerability (CVE-2017-11882). The presence of RTF_OBJDATA, RTF_OBJAUTLINK, RTF_OBJUPDATE, and specifically the RTF_EQUATION_EDITOR heuristic, along with the ClamAV detection name, strongly indicates exploitation of this known vulnerability. This technique is commonly used to deliver a second-stage payload.

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
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000005e.bin
eb8a99b8ecbfa97dde83846dbe0527f229038e56924fe988737897098926382e
rtf-objdata-decoded RTF \objdata at offset 0x5E 4150 bytes