Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 8d9c7163a2209cb7…

MALICIOUS

Office (OLE)

175.0 KB Created: 2020-05-13 10:36:24 Authoring application: Microsoft Excel First seen: 2020-07-24
MD5: 1a0e94cdba0607a83fd1f618a562c429 SHA-1: 3f50d6fea57cdb2f74a14ba7dea966741187beb5 SHA-256: 8d9c7163a2209cb725f061a951ce38a871eb57d891be1e8b892e8ecda3c89c2b
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The file contains Excel 4.0 macros, specifically an Auto_Open defined name, which is a known method for executing malicious code when the workbook is opened. The presence of dangerous formula APIs like RUN (25) indicates an intent to execute arbitrary commands or payloads. No specific family could be identified, but the technique is common for initial execution.

Heuristics 3

  • Excel 4.0 Auto_Open defined name critical OLE_XLM_AUTOOPEN_DEFINEDNAME
    oletools recovered an Auto_Open / Auto_Close entry from an Excel 4.0 macro sheet. The raw BIFF name can be tokenized or partially opaque to byte-string checks, but the recovered macro listing confirms the workbook has an XLM auto-execution entry.
  • XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • Excel 4.0 (XLM) macro sheet present medium OLE_XLM_AUTOOPEN
    Workbook contains an Excel 4.0 macro sheet sub-stream — XLM is rarely seen in modern legitimate workbooks and was a major Office malware vector during 2020-2022.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 126471 bytes
SHA-256: fbbda4a21e1d06ba685d92fe64155d09cef13eb3505ffb4df844edc55dcaf96e
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     14 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  Sheet
' 0018     28 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open hidden len=7 ptgRef3d  Sheet!J65077 
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' Sheet,Reference,Formula,Value
'  Sheet,EG28,"",3010.00000000000000000000
'  Sheet,HK59,"",-34.79999999999999715783
'  Sheet,BV78,"",0.59756097560975607319
'  Sheet,EM94,"",-0.34156378600823045222
'  Sheet,CC116,"",-1.63865546218487390107
'  Sheet,DR118,"",-0.35384615384615386580
'  Sheet,CC130,"",-26.00000000000000000000
'  Sheet,GK170,"",-0.03872153872053871876
'  Sheet,BL202,"",0.67455621301775148257
'  Sheet,IJ207,"",-2.93636363636363650897
'  Sheet,JF220,"",-6.97101449275362305968
'  Sheet,CX227,"",-0.13897488820089440309
'  Sheet,GF269,"",1505.00000000000000000000
'  Sheet,EK332,"",-0.32929782082324454695
'  Sheet,ES338,"",3.88888888888888883955
'  Sheet,EC381,"",-582.00000000000000000000
'  Sheet,CC388,"",-2.33193377310924354617
'  Sheet,JN407,"",-0.05995717344753747485
'  Sheet,GO458,"",-0.08316008316008316470
'  Sheet,BM507,"",0.16833333333333333481
'  Sheet,DM533,"",-0.01380471380471380398
'  Sheet,FV598,"",-554.00000000000000000000
'  Sheet,FV658,"",-9.31730769230769162448
'  Sheet,FD662,"",4.72222222222222232091
'  Sheet,DZ704,"",-7.88524590163934391285
'  Sheet,CK801,"",533.00000000000000000000
'  Sheet,IG835,"",-0.06566738044254104290
'  Sheet,GA852,"",60.00000000000000000000
'  Sheet,HI956,"",3062.00000000000000000000
'  Sheet,CH1036,"",57.00000000000000000000
'  Sheet,CV1038,"",-6.97101449275362305968
'  Sheet,FG1052,"",-262.00000000000000000000
'  Sheet,BZ1093,"",13.63636363636363668661
'  Sheet,EJ1100,"",0.77272727272727270709
'  Sheet,IP1271,"",116.60007812499999602096
'  Sheet,HS1273,"",-0.42660550458715595923
'  Sheet,DX1341,"",0.45000030517578126776
'  Sheet,BJ1378,"",441.00000000000000000000
'  Sheet,ED1397,"",-162.60007812500001023182
'  Sheet,JG1427,"",-6.39462365591397929876
'  Sheet,DK1434,"",0.20118343195266272239
'  Sheet,GB1596,"",-0.13897488820089440309
'  Sheet,EO1619,"",-41.20588235294117396279
'  Sheet,FA1642,"",-3039.00000000000000000000
'  Sheet,EQ1652,"",170.25000000000000000000
'  Sheet,IP1688,"",642.70000000000004547474
'  Sheet,GK1769,"",-710.70062499999994543032
'  Sheet,FX1794,"",-401.00000000000000000000
'  Sheet,FF1813,"",-117.00000000000000000000
'  Sheet,BH1835,"",-1.00840336134453778527
'  Sheet,FU1839,"",1.41463414634146333881
'  Sheet,BI1849,"",-0.07398788414326550045
'  Sheet,CM1963,"",3075.00000000000000000000
'  Sheet,JA1993,"",551.00000000000000000000
'  Sheet,BD2015,"",0.47953216374269003186
'  Sheet,HC2017,RUN(FD50425),""
'  Sheet,DV2074,"",-9.55882352941176449690
'  Sheet,GI2122,"",-3015.00000000000000000000
'  Sheet,EC2155,"",-179.75000000000000000000
'  Sheet,BQ2253,"",0.33666666666666666963
'  Sheet,GM2335,"",-9.82094594594594560988
'  Sheet,JH2335,"",-0.01346801346801346742
'  Sheet,DW2401,"",-4.11392405063291111134
'  Sheet,HO2430,"",-8.60000000000000142109
'  Sheet,CR2461,"",-407.00000000000000000000
'  Sheet,ES2506,"",-243.80015624999998635758
'  Sheet,BE2523,"",5.02941176470588224845
'  Sheet,GO2524,"",-0.16615384615384615197
'  Sheet,IL2525,"",-6.37254901960784270187
'  Sheet,CY2541,"",401.00000000000000000000
'  Sheet,GY2547,"",-760.75000000000000000000
'  Sheet,CJ2561,"",-224.25000000000000000000
'  Sheet,DR2594,"",770.75000000000000000000
'  Sheet,F2661,"",-0.28000000000000002665
'  Sheet,U2675,"",2.55223880597014929350
'  Sheet,W2690,"",0.36396396396396396566
'  Sheet,HG2691,"",2.19999999999999973355
'  Sheet,ED2745,"",-376.00000000000000000000
'  Sheet,BP2757,"",267.80015624999998635758
'  Sheet,CL2792,"",-0.14629224819236588684
'  Sheet,CQ2809,"",-0.18664873045232888149
'  Sheet,FQ2865,"",-0.02855103497501784368
'  Sheet,CF2885,"",-0.24324324324324325675
'  Sheet,EN2929,"",1468.00000000000000000000
'  
... (truncated)