Malicious RTF — malware analysis report

Static analysis result for SHA-256 de76d84ae9eb617f…

MALICIOUS

RTF

12.9 KB
MD5: e2c1faf78a91f45c6f641d24d639865d SHA-1: 7d24665d6cf8abc56649f627439ce35ad9f3f6f5 SHA-256: de76d84ae9eb617fd8e9c19f0650374a2021d5188f41105781824b9939903fbc
120 Risk Score

Malware Insights

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

The sample is an RTF document that contains an embedded OLE object, specifically targeting the Equation Editor vulnerability. The ".objupdate" directive indicates that the OLE object is designed to be activated automatically upon opening the document. This exploit is commonly used to download and execute a secondary payload, leading to a full system compromise. The presence of the Equation Editor exploit and the OLE object strongly suggests a malicious intent to deliver further malware.

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 1 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000018b6.bin
e09424f4bd41d0d6593cffa660f57b772e4463b0b3946c1d3359b6f6c2bf18c3
rtf-objdata-decoded RTF \objdata at offset 0x18B6 2066 bytes