Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5024236981d1fb0…

MALICIOUS

PDF

195.3 KB Created: 2010-06-29 10:30:35 +08:00 First seen: 2013-08-29
MD5: ea02baa7b39338f3fbfc575fb1a786e2 SHA-1: 5b5b76ac805fa29112a954304fe47a797882ff5f SHA-256: b5024236981d1fb0f0504e6fd07675eab5e66723434ce84fd1c329431129f78c
498 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file contains JavaScript that exploits CVE-2009-4324, a vulnerability in Adobe Reader related to media player handling. The heuristic firings indicate the use of JavaScript and potential exploitation of this specific CVE. The embedded stream and secondary PDF suggest a multi-stage attack designed to download and execute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8819

Heuristics 13

  • Adobe Flash Player RichMedia exploit critical CVE likely CVE_2011_0611_FLASH_RICHMEDIA
    PDF combines RichMedia Flash activation with an embedded AS3 SWF loader (ByteArray/loadBytes) and shellcode heap-spray staging. This is the static exploit shape associated with CVE-2011-0611 Flash content delivered through Adobe Reader.
  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • Flash ActionScript-3 exploit loader in PDF critical CVE related PDF_FLASH_AS3_EXPLOIT_LOADER
    An embedded Flash (SWF) object's ActionScript-3 bytecode contains exploit-loader primitives: decompressing an inner SWF into a ByteArray and executing it via LoaderContext.allowLoadBytesCodeExecution, and/or Vector heap/JIT spray groomers. Benign Flash content does not load and execute code from raw bytes — this is a staged Flash exploit delivered through the document.
  • ClamAV: Pdf.Dropper.Agent-7115670-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7115670-0
  • 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. (matched inside decoded stream)
  • 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.
    Matched line in script
     var nop =  unescape("\x25\x750c0c");
  • 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. (matched inside decoded stream)
  • RichMedia (Flash) high PDF_RICHMEDIA
    PDF contains /RichMedia (Adobe Flash) which is a historic exploit vector (matched inside decoded stream)
  • Secondary embedded PDF body has suspicious static findings high POLYGLOT_CHILD_PDF_STATIC_TRIAGE
    A valid PDF body was found at a nonzero offset inside another container and its carved contents matched PDF exploit or lure heuristics. This catches polyglots where the top-level magic routes to ZIP/OLE while a PDF reader or downstream parser opens the hidden PDF payload.
  • 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 file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload (matched inside decoded stream)
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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.w3.org/1999/02/22-rdf-syntax-ns# In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/pdfx/1.3/In PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off00000392.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x392 4147 bytes
SHA-256: 3fe2798dee710afba1b76a5a4e58ef9bcaadaac71686d8cd1def22be35686c45
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 3 long base64-like blob(s). Carved artifact contains 1 long hex-escaped blob(s).
legacy_pdfkit_stage_000.js deobfuscated-js string-concatenation normalized Acrobat API aliases at offset 0x392 126 bytes
SHA-256: 42c3f4df375ff6f58ff655cc4f88b5cc28f0dd33b978390db3538684a6219b74
Preview script
First 1,000 lines of the extracted script
media.newPlayer(null); /* AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA */
objstm_0017_00.bin pdf-objstm-decoded PDF /ObjStm 17 0 obj (inflated) 871 bytes
SHA-256: dd7918c182d6e2b8d996a6b8ee81663c49a0cb297efe1e1fa3c5af0c987bde84
font_00_sfnt_off0002b221.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2B221 146696 bytes
SHA-256: ec90d77f6b6fa94783e0acb6b489b8d28e8ce7aef6f9d15fb07bf2aeb3cde640
polyglot_child_pdf_off0002088f.pdf polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x2088F 66737 bytes
SHA-256: cf4f71f8e08fdee1dc0fe4c99b1a8f3d75a58b7ed461f6e3e4d81b950a44a827