Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf8af03d25dc9401…

MALICIOUS

PDF

385.6 KB Created: 2012-05-10 22:18:44 +02:00 Authoring application: Microsoft® Word 2010 First seen: 2015-10-01
MD5: c0845766f6b9d0395e185e8e6c99e890 SHA-1: 70b0fd38007ed97d6bc72d79728c4ddce7d09c28 SHA-256: cf8af03d25dc94015d6cc8e98d95456e99e6fe57b1ddd5e0a163bdd6e7a479b6
718 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.003 Windows Command Shell T1105 Ingress Tool Transfer

This PDF file contains embedded JavaScript and a PE payload, and triggers a launch action for cmd.exe. This indicates an attempt to exploit a vulnerability, likely CVE-2010-1240, to execute arbitrary code. The embedded executable and the associated URL suggest the document is a lure to download and run a secondary malicious payload. The ClamAV detection further confirms its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 16

  • 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.
  • TrueType bitmap font + active content — CVE-2023-26369 related high CVE related PDF_CVE_2023_26369_RELATED
    PDF embeds a TrueType font with bitmap tables (EBDT/sbix/CBDT) alongside exploit delivery indicators — CVE-2023-26369 exploits the sfac_GetSbitBitmap function in Adobe's libCoolType for arbitrary code execution. This CVE was actively exploited in the wild, but this rule does not validate the malformed EBLC/EBDT primitive.
  • 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\\!Infected_PDF_File_WARNING!!!.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.
  • JavaScript action low 2 related findings PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • 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.
  • /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.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • External URI info 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://blog.snypter.com/2011/10/adobe-pdf-embedded-exe-exploit-for-xp-systems/ PDF link annotation
    • http://www.zeustech.net/Referenced by PDF JavaScript
    • http://]hostname[:port]/pathIn extracted file (Infected_PDF_File_WARNING.pdf)
    • tcp://0.0.0.0:4444In extracted file (Infected_PDF_File_WARNING.pdf)
    • http://www.apache.org/Referenced by PDF JavaScript
    • http://www.microsoft.com/typography/ctfontshttp://fontfabrik.comYouIn extracted file (stream_004_off000176d0.bin)
    • http://www.microsoft.com/typography/fonts/default.aspxIn extracted file (stream_004_off000176d0.bin)
    • http://crl.microsoft.com/pki/crl/products/CSPCA.crl0HIn extracted file (stream_004_off000176d0.bin)
    • http://www.microsoft.com/pki/certs/CSPCA.crt0In extracted file (stream_004_off000176d0.bin)
    • http://crl.microsoft.com/pki/crl/products/tspca.crl0HIn extracted file (stream_004_off000176d0.bin)
    • http://www.microsoft.com/pki/certs/tspca.crt0In extracted file (stream_004_off000176d0.bin)
    • http://www.microsoft.com/typographyIn extracted file (stream_004_off000176d0.bin)

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
Infected_PDF_File_WARNING.pdf pdf-embedded-file PDF EmbeddedFile object 64 at offset 0x55458 73802 bytes
SHA-256: a1386d99ecca30ee93312680ff03c2c219cc3970c1b37209995ef7951fa8429c
Detection
ClamAV: Win.Trojan.Swrort-5710536-0
Obfuscation or payload: likely
actual_type=PE; declared_or_context_type=PDF; filename=Infected_PDF_File_WARNING.pdf; kind=pdf-embedded-file Static shellcode analysis recovered the Metasploit stager connect-back address: 0.0.0.0:4444 (reverse/x86, bind-any) Static shellcode analysis found candidate code region(s). Indicators: SC_PEB_ACCESS, SC_MSF_BIND, SC_PUSH_STRING Static shellcode analysis recovered API/import strings: kernel32.dll, advapi32.dll, KERNEL32.DLL, ADVAPI32.DLL, LoadLibraryA, GetProcAddress
javascript_obj0065_000.js pdf-javascript-stream PDF /JS object 65 at offset 0x600D0 78 bytes
SHA-256: 55fd770131edfae6dad9cfc3bf2e6daf23ccc9be8bed99a6bfd99922e422c9ab
Preview script
First 1,000 lines of the extracted script
this.exportDataObject({ cName: "!Infected_PDF_File_WARNING!!!", nLaunch: 0 });
stream_004_off000176d0.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x176D0 188552 bytes
SHA-256: 5c1d9757cab5cca7cc965b4f77b6c89ea1cf0f3961157e2d387840caf852e0a5
font_00_sfnt_off00001edd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1EDD 184856 bytes
SHA-256: a89350e23a95cde3edcfd067cf1348316d5c6d3b8a283e6fbf36f55d7921d8e1
font_02_sfnt_off0002d454.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2D454 165360 bytes
SHA-256: f71051a019c4fbf333391e1e483d391a511704d1f1aa3249d0cc2ce1f7c9ba40
font_03_sfnt_off00040493.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x40493 175112 bytes
SHA-256: 65b03189ae28e5c312a2feb6dd162794397cfc94fa930918fde3be157d9eb5a8