Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 6cc35b78c42786d3…

MALICIOUS

RTF / .DOC

17.8 KB
MD5: b9106596c3fe8f0cbfe52d05f3e932e7 SHA-1: 592be243de22c72feede60345b5dc38f5f331995 SHA-256: 6cc35b78c42786d3121bee8df47326cf744c0a123c075d7da67c2dfdf6929055
120 Risk Score

Malware Insights

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

The sample is an RTF document that contains embedded OLE objects and triggers the Equation Editor vulnerability. This indicates an attempt to exploit a client-side vulnerability for code execution. The presence of ".objupdate" suggests that the embedded object is activated automatically, likely to download and execute a secondary payload. No specific family could be identified, but the exploit method is common for initial compromise.

Heuristics 3

  • 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 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000589.bin
6f14b21aee5add538c796e2681abf4727b8851fd683ec76d2f3a15478b0372ff
rtf-objdata-decoded RTF \objdata at offset 0x589 1867 bytes