Malicious PDF — malware analysis report

Static analysis result for SHA-256 2973675f1c9fb152…

MALICIOUS

PDF

50.1 KB Created: 2010-03-17 15:16:21 +08:00 Authoring application: Converting... First seen: 2013-08-20
MD5: ad0b7237cd7ea338f06ddd25ac414efd SHA-1: 607c2b999ef4acf72e743f3a2a78487ffc181fee SHA-256: 2973675f1c9fb152160ce7f605c84a06e82ca8ec04ee10566a37e96da1af0985
290 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link or Macro: User Execution: Malicious Link T1204.002 Malicious Link or Macro: User Execution: Malicious Macro

The PDF file contains embedded JavaScript that exploits CVE-2009-4324, a known vulnerability in Adobe Reader. The heuristic firings indicate the presence of JavaScript actions and the use of unescape() for obfuscation, consistent with exploit kit techniques. The embedded JavaScript is likely responsible for downloading and executing a second-stage payload, although the specific URL or payload could not be reconstructed from the provided evidence. The polyglot nature of the PDF, containing secondary embedded PDFs, further suggests a multi-stage attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9841

Heuristics 8

  • 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)
  • Secondary embedded PDF body has suspicious static findings critical 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.
  • 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 sc =  unescape(urpl("%Zc8d9%Z74d9%Zf424%Zeeba%Ze0ec%Z29de%Z5fc9%Z37b1%Z5731%Z8314%Z1001%Z2602%Z4207%Zdee0%Z55ee%Zdee4%Zecee%Zbabf%Zdc4f%Zdee0%Z67ee%Zd2a0%Z9c65%Z73fc%Z8465%Z8fe8%Z9965%Z55dc%Zc29a%Zdd98%Zba1b%Za86b%Zefce%Zed15%Za527%Z73a1%Z29ed%Z05d3%Z52e1%Ze6f0%Z981c%Z1fe8%Ze125%Z04e3%Z07ae%Ze511%Z99f1%Z8007%Zb265%Zddc4%Z8a33%Zd26b%Z67a5%Zc2be%Z31ed%Zda6b%Zef65%Z7525%Z0eb7%Zed5c%Z6f35%Zda23%Zec84%Z21b3%Z10b9%Zd9db%Z1f9b%Z8169%Z7512%Z8cb2%Z9b11%Z21e4%Z1099%Z891f%Z7516%Z9e8a%Zec86%Zdef0%Z13ee% …
  • 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)
  • 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.
  • 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://www.iec.chIn PDF document text

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000063a.js decompressed-pdf-stream PDF FlateDecoded stream at offset 0x63A 2578 bytes
SHA-256: 4e2eb1a8bcbf2ad030463ba8e27e4bc8634f01b8d30c1f1731daa28e9d5aac09
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(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 0x63A 126 bytes
SHA-256: 42c3f4df375ff6f58ff655cc4f88b5cc28f0dd33b978390db3538684a6219b74
Preview script
First 1,000 lines of the extracted script
media.newPlayer(null); /* AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA */
objstm_0023_00.bin pdf-objstm-decoded PDF /ObjStm 23 0 obj (inflated) 274 bytes
SHA-256: e8bfe65c34a535b0837ce7c541e45b42ab61e1ff13de05788daf7770f9a1ec0e
icc_00_off0000a428.icc pdf-icc-profile PDF ICC profile at offset 0xA428 3144 bytes
SHA-256: 2b3aa1645779a9e634744faf9b01e9102b0c9b88fd6deced7934df86b949af7e
polyglot_child_pdf_off000097d3.pdf polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x97D3 12423 bytes
SHA-256: 2c76dfa59200bf51b29a7b7ebe44e0a003a6024d2289113fe41884dba89e2406
polyglot_child_pdf_off0000b06d.pdf polyglot-child-pdf Secondary PDF body inside pdf container at offset 0xB06D 6125 bytes
SHA-256: 0b1c923c8a0028794f3a3244dc498786746334f394e41678cc58ffbeb707d0a8