Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 ca2d2e291eb8a21e…

MALICIOUS

RTF / .DOC

27.9 KB First seen: 2022-12-12
MD5: fc20f1f2466a37264a5551951aa0b6fa SHA-1: 6c59f7f1d2b4adb182d8ec310d6c414f7b79fe70 SHA-256: ca2d2e291eb8a21ef82658012626da0a3c0030e4db5e1d6e02f81a36bfb4d42d
140 Risk Score

Malware Insights

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

The sample is an RTF document containing an embedded OLE object with an Equation Editor ProgID, a known exploit vector. The document body contains a lure instructing the user to 'Enable editing' to view the content. This combination strongly suggests an attempt to exploit a vulnerability, likely CVE-2017-11882, to execute a malicious payload.

Heuristics 4

  • Split hex Equation Editor ProgID + OLE object critical RTF_EQUATION_EDITOR
    RTF embeds the Equation.3 ProgID as hex bytes near OLE object activation and splits the byte stream with whitespace or an ignorable RTF group. This is an Equation Editor OLE activation surface commonly used by CVE-2017-11882 / CVE-2018-0802 exploit documents.
  • \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
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000480c.bin
153e3c625f6f17b4482eaa53005bb982e302e2d24719b1cc0a2d70bcd86f3b7c
rtf-objdata-decoded RTF \objdata at offset 0x480C 1444 bytes