Malicious PDF — malware analysis report

Static analysis result for SHA-256 daf8d499e0e20741…

MALICIOUS

PDF

140.2 KB First seen: 2015-09-20
MD5: 199cf4018eae0a7376ac576b13d1c400 SHA-1: a764db43e98a098ed2fecde27bcff3fcb9314892 SHA-256: daf8d499e0e207416c985a8803517bdda77e8ce9e16a43523bbb8d4772eac76d
624 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF file contains JavaScript that attempts to export a data object named 'test'. This action is paired with a PDF launch action that executes 'cmd.exe', indicating an attempt to exploit CVE-2010-1240 to execute a payload. The embedded artifact 'test.pdf' was identified as a Windows executable, further confirming the malicious intent to deliver and execute a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 14

  • Adobe Reader Launch action command execution critical CVE exact CVE_2010_1240
    PDF uses the Adobe Reader/Acrobat Launch action pattern associated with CVE-2010-1240: cmd.exe is invoked with attacker-controlled parameters, paired with an embedded/exported payload.
  • ClamAV: Pdf.Tool.Agent-1388586 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Tool.Agent-1388586
  • Launch action critical PDF_LAUNCH
    PDF contains a /Launch action whose target is an executable, URL, or UNC path — can start an external application
  • Embedded Windows executable payload in PDF stream critical PDF_EMBEDDED_PE_PAYLOAD
    PDF stream bytes contain an embedded Windows executable with a verified PE header. Exploit chains often hide droppers inside ordinary streams rather than standard /EmbeddedFile attachments.
  • /Launch action target: cmd.exe critical PDF_LAUNCH_COMMAND
    PDF /Launch action specifies an executable target with parameters '/Q /C %HOMEDRIVE%&cd %HOMEPATH%&(if exist "Desktop\\test.pdf" (cd "Desktop"' — references a known-dangerous executable (cmd, PowerShell, etc.).
  • Embedded attachment masquerades: declared document, content is windows-executable critical PDF_EMBEDDED_FILESPEC_CONTENT_MISMATCH
    An /EmbeddedFile attachment's declared filename extension or /Subtype MIME type contradicts the magic bytes of its decompressed content. The attachment is declared as a benign document or image but the bytes are an executable or executable-bearing archive. This is a deliberate deception used to hide droppers in PDF attachments and is a generic indicator of embed-and-drop weaponisation, independent of any specific CVE.
  • Suspicious extracted artifact critical 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.
  • /Launch action paired with attachment-dropping JS API high PDF_LAUNCH_PLUS_DROPPER_JS
    PDF combines a /Launch action with a JavaScript API call that writes or opens an attached/external resource — the canonical shape of the CVE-2010-1240 /Launch + exportDataObject family. Benign PDFs do not pair these surfaces; the combination indicates a drop-and-execute chain regardless of the specific JS API knobs or /Launch target.
  • Clickable PDF combines external action with parser-evasion structure high PDF_ACTION_PARSER_EVASION
    PDF has an external clickable URI together with object graph or xref structures that make parsers disagree, such as divergent duplicate objects, parser divergence, or xref offset mismatch. That combination is stronger than a plain link: the document is both an outward-action carrier and a parser-confusion/evasion sample.
  • JavaScript action low 1 related finding PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • External URI low PDF_URI
    PDF contains an external URL action
  • 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://www.zeustech.net/ Referenced by PDF JavaScript
    • http://]hostname[:port]/pathIn extracted file (test.pdf)
    • tcp://192.168.147.142:257In extracted file (test.pdf)
    • http://www.afterdawn.com/glossary/terms/conditional_access_module.cfmPDF link annotation
    • http://www.afterdawn.com/glossary/terms/conditional_access_system.cfmIn PDF document text
    • http://www.afterdawn.com/glossary/terms/conditional_access_module.cfm)endobj19In PDF document text
    • http://www.afterdawn.com/glossary/terms/conditional_access_system.cfm)endobj9In PDF document text
    • http://www.apache.org/Referenced by PDF JavaScript
    • http://www.iec.chIn extracted file (icc_00_off0000b62a.icc)

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
test.pdf pdf-embedded-file PDF EmbeddedFile object 52 at offset 0x18031 73802 bytes
SHA-256: b85f240d8964eda2cd82ef52ee4d8f428b2c5cec0340ac0499c7203044c6b0bf
Detection
ClamAV: Win.Trojan.MSShellcode-7
Obfuscation or payload: likely
actual_type=PE; declared_or_context_type=PDF; filename=test.pdf; kind=pdf-embedded-file Static shellcode analysis recovered the Metasploit stager connect-back address: 192.168.147.142:257 (reverse/x86, lab (non-routable)) Static shellcode analysis found candidate code region(s). Indicators: SC_PEB_ACCESS, SC_MSF_REVERSE, SC_PUSH_STRING Static shellcode analysis recovered API/import strings: kernel32.dll, advapi32.dll, KERNEL32.DLL, ADVAPI32.DLL, LoadLibraryA, GetProcAddress
javascript_obj0053_000.js pdf-javascript-stream PDF /JS object 53 at offset 0x22CB3 53 bytes
SHA-256: b1a09f919e0f5d1c1d284849c9af93bae6fd1411634dfdc491e126f9cd327f3f
Preview script
First 1,000 lines of the extracted script
this.exportDataObject({ cName: "test", nLaunch: 0 });
stream_007_off0000d99c.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xD99C 28748 bytes
SHA-256: 7af40e8778d002cc3fc1564a190e9d8643f068cefd9cf1da8934adac4b2837f7
icc_00_off0000b62a.icc pdf-icc-profile PDF ICC profile at offset 0xB62A 3144 bytes
SHA-256: 2b3aa1645779a9e634744faf9b01e9102b0c9b88fd6deced7934df86b949af7e
icc_01_off0000c0ff.icc pdf-icc-profile PDF ICC profile at offset 0xC0FF 4380 bytes
SHA-256: bad673993556e6b0887d39ea77607649277a6ccaa6a2d454ec077dad52adc122
font_01_sfnt_off00012d08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D08 6780 bytes
SHA-256: 6e28b485e52e02cd3776de5f6910482cd52337d749fddb0c950b554f588e8167
font_02_sfnt_off000141cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141CF 19520 bytes
SHA-256: 918283255c3352ee70016b40338614216d29cc719387b49bfbfecb255d021109