Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 ef1a302237627683…

MALICIOUS

Office (OLE)

729.1 KB Created: 2007-08-13 02:12:00 Authoring application: Microsoft Office Word First seen: 2015-09-30
MD5: abd26ad3c7fecef42a19fd2a5ad97d20 SHA-1: e2fb737708543f7f7cee042fc670629a536af60d SHA-256: ef1a30223762768331c53a8bcfcaa6a21fb61852c1412bc759889f76930a1ec9
922 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell T1059.003 Windows Command Shell

The sample is a malicious Microsoft Word document that exploits CVE-2007-3899 and CVE-2008-2244 to embed and execute a PE executable. Heuristics indicate the use of WinExec, CreateProcess, ShellExecute, URLDownloadToFile, VirtualAlloc, VirtualProtect, WriteProcessMemory, CreateRemoteThread, LoadLibrary, and GetProcAddress, suggesting a complex payload execution chain. The embedded PE executable, detected by ClamAV as Win.Malware.Razy-9886340-0, is the primary malicious component.

Heuristics 20

  • CVE-2007-3899 — Microsoft Word malformed string memory corruption critical CVE likely CVE_2007_3899
    Word OLE document has the MS07-060 malformed-string exploit shape: a Word 97-family FIB points to a malformed DOP/string-table region with an abnormal INT_MAX run, inflated text counters, and exploit payload or Mdropper.Z campaign evidence.
  • CVE-2008-2244 — Microsoft Word record-parsing payload critical CVE likely CVE_2008_2244
    Word OLE document has normal small WordDocument/table streams, a large unallocated OLE slack region, and an executable or resolver shellcode payload in that slack. This is the static shape of the MS08-042 Word record-parsing exploit family tracked as CVE-2008-2244.
  • ClamAV: Win.Malware.Razy-9886340-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Malware.Razy-9886340-0
  • Reference to URLDownloadToFile API critical SC_STR_URLDOWNLOAD
    Reference to URLDownloadToFile API
  • Reference to WriteProcessMemory API critical SC_STR_WRITEPROCESSMEMORY
    Reference to WriteProcessMemory API
  • Reference to CreateRemoteThread API critical SC_STR_CREATEREMOTETHREAD
    Reference to CreateRemoteThread API
  • Embedded PE executable critical OLE_EMBEDDED_EXE
    MZ/PE header found inside document — possible embedded executable
  • Embedded Office document has suspicious static findings critical EMBEDDED_OFFICE_CHILD_STATIC_TRIAGE
    A CFB/OLE Office document was found inside another file type and its carved contents matched Office exploit or payload heuristics. This catches wrapped exploit documents where the top-level file routes to a PE, archive, or generic scanner instead of Office.
  • x86 GetPC stub (CALL $+5; POP EDX) high SC_GETPC_CALL
    x86 GetPC stub (CALL $+5; POP EDX)
    Disassembly
    Attempted x86 opcode disassembly
    0002CC72  e800000000        call 0x2cc77
    0002CC77  5a                pop edx
    0002CC78  ffc2              inc edx
    0002CC7A  0fc0c1            xadd cl, al
    0002CC7D  e800000000        call 0x2cc82
    0002CC82  5a                pop edx
    0002CC83  f7d2              not edx
    0002CC85  0fafd7            imul edx, edi
    0002CC88  0fbeca            movsx ecx, dl
    0002CC8B  d1f2              sal edx, 1
    0002CC8D  0fafd1            imul edx, ecx
    0002CC90  f6d8              neg al
    0002CC92  bab983e049        mov edx, 0x49e083b9
    0002CC97  69c88060c309      imul ecx, eax, 0x9c36080
    0002CC9D  8d15d1abaefa      lea edx, [0xfaaeabd1]
    0002CCA3  85ce              test esi, ecx
    0002CCA5  eb07              jmp 0x2ccae
    0002CCA7  21ca              and edx, ecx
    0002CCA9  17                pop ss
    0002CCAA  98                cwde
    0002CCAB  1db6b3e800        sbb eax, 0xe8b3b6
    0002CCB0  0000              add byte ptr [eax], al
    0002CCB2  005a85            add byte ptr [edx - 0x7b], bl
    0002CCB5  ce                into
    0002CCB6  86c1              xchg cl, al
    0002CCB8  0fc1d0            xadd eax, edx
    0002CCBB  2cc3              sub al, 0xc3
    0002CCBD  31fa              xor edx, edi
    0002CCBF  8ac2              mov al, dl
    0002CCC1  0fafd7            imul edx, edi
    0002CCC4  f6c6b3            test dh, 0xb3
    0002CCC7  e800000000        call 0x2cccc
    0002CCCC  5a                pop edx
    0002CCCD  c3                ret
    0002CCCE  0000              add byte ptr [eax], al
    0002CCD0  0000              add byte ptr [eax], al
  • Reference to WinExec API high SC_STR_WINEXEC
    Reference to WinExec API
  • Reference to CreateProcess API high SC_STR_CREATEPROCESS
    Reference to CreateProcess API
  • Reference to ShellExecute API high SC_STR_SHELLEXEC
    Reference to ShellExecute API
  • Reference to LoadLibrary API high SC_STR_LOADLIBRARY
    Reference to LoadLibrary API
  • Reference to GetProcAddress API high SC_STR_GETPROCADDRESS
    Reference to GetProcAddress API
  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 746,606 bytes but its declared streams total only 18,208 bytes — 728,398 bytes (98%) live in unallocated sector slack. This is the canonical hiding place for pre-macro-era Office exploit payloads (XOR-encoded shellcode reached via a parser pointer-corruption bug in the document structure).
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • Reference to VirtualAlloc API medium SC_STR_VIRTUALALLOC
    Reference to VirtualAlloc API
  • Reference to VirtualProtect API medium SC_STR_VIRTUALPROTECT
    Reference to VirtualProtect API
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://upx.tsx.org In document text (OLE body)
    • http://microsoft.com0In document text (OLE body)
    • http://crl.microsoft.com/pki/crl/products/CSPCA.crl0HIn document text (OLE body)
    • http://www.microsoft.com/pki/certs/CSPCA.crt0In document text (OLE body)
    • http://crl.microsoft.com/pki/crl/products/tspca.crl0HIn document text (OLE body)
    • http://www.microsoft.com/pki/certs/tspca.crt0In document text (OLE body)
    • http://go.microsoft.com/fwlink/?LinkId=96782ARPNOMODIFYARPURLUpdateInfohttp://go.microsoft.com/fwlink/?LinkId=96789comspec_cmd%comspec%DDPatchDiskNo1[DiskIn document text (OLE body)

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_office_0002b96f.exe embedded-pe Office MZ+PE at offset 0x2B96F 568063 bytes
SHA-256: 4ee1a24b65e21d84af09a84042e14fa77ae4b033dbaaeb660cd63a4829111e79
Detection
ClamAV: Win.Malware.Razy-9886340-0
Obfuscation or payload: likely
Static shellcode analysis found candidate code region(s). Indicators: SC_GETPC_CALL, SC_STR_GETPROCADDRESS, SC_STR_LOADLIBRARY Static shellcode analysis recovered API/import strings: GetProcAddress, LoadLibraryA, VirtualProtect, CreateRemoteThread, VirtualAlloc, VirtualAllocEx
embedded_office_off0000560d.ole embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x560D 724577 bytes
SHA-256: cc2f37258b372b1fb18e80d3a3111260fab58329a56666db12e3a9db359d9160
Detection
ClamAV: Win.Malware.Razy-9886340-0
Obfuscation or payload: likely
Static shellcode analysis found candidate code region(s). Indicators: SC_GETPC_CALL, SC_STR_GETPROCADDRESS, SC_STR_LOADLIBRARY Static shellcode analysis recovered API/import strings: GetProcAddress, LoadLibraryA, VirtualProtect, CreateRemoteThread, VirtualAlloc, VirtualAllocEx
embedded_office_00002a00.exe embedded-pe Office MZ+PE at offset 0x2A00 295896 bytes
SHA-256: 5241f8713bf506539b733ff12ef20e4a39bff6a45720a638020a0b1baadc88f9
Detection
ClamAV: Win.Malware.Razy-9886340-0
Obfuscation or payload: unlikely
embedded_office_off0006b696.ole embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x6B696 306648 bytes
SHA-256: b0d33837444eb7d0ae2ea084efd543534befa09c76d204f9aadd2b2c1945b79a
Detection
ClamAV: Win.Malware.Razy-9886340-0
Obfuscation or payload: unlikely