RTF malware analysis — malicious · bf81e43ddb79536b

MALICIOUS

RTF

6.6 KB First seen: 2019-03-10

MD5: 677adc07e064701a3b6bc7ab6e5f1f4f SHA-1: 7d1cc26df8c1f7eb6b364493ac37f398a6ea9830 SHA-256: bf81e43ddb79536b33f6094be91eddf39e6cdaeb95c270d5d5d73b85ee416317

220 Risk Score

Malware Insights

MITRE ATT&CK

T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF document contains an embedded OLE object specifically identified as an Equation Editor object, triggering heuristics related to CVE-2017-11882. This indicates the document is designed to exploit this known vulnerability for client-side code execution. The presence of ".bin" file in the extracted artifacts suggests a potential shellcode payload.

Heuristics 6

Split hex Equation Editor ProgID + OLE object critical CVE likely 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.
Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED

RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
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
Suspicious extracted artifact medium EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`objdata_00_off00000b15.bin`	rtf-objdata-decoded	RTF \objdata at offset 0xB15	1980 bytes
SHA-256: `51d732cb13b32a532914ba817565d6af5fa3987981042581daf798fa552c5567`
Detection ClamAV: No threats found Obfuscation or payload: likely Static shellcode analysis found candidate code region(s). Indicators: SC_GETPC_CALL

Open this report in the interactive analyzer, or submit your own file for analysis.