Malicious PDF — malware analysis report

Static analysis result for SHA-256 591e72610db5c800…

MALICIOUS

PDF

79.2 KB Created: 2010-03-15 09:35:32 +08:00 Authoring application: Writer (via OpenOffice.org 2.2)
MD5: 773ab422279236359aa44660f09fc371 SHA-1: 63972e959f59dfeedaeed4bb31add05b8bfd9c78 SHA-256: 591e72610db5c8007cc9fb663c1cefacf0995c4f7e1ec11b809f463609d49a8c
196 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript that leverages the CVE-2009-4324 vulnerability through the media.newPlayer API. This JavaScript is designed to download and execute a secondary malicious PDF, as indicated by the 'POLYGLOT_CHILD_PDF_STATIC_TRIAGE' heuristic. The obfuscated JavaScript and the use of a known exploit point to a downloader or exploit kit stage.

Heuristics 7

  • 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.
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (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.
  • JavaScript action low 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)
  • 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)
  • 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#
    • http://ns.adobe.com/xap/1.0/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/pdf/1.3/

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000063a.js
9ca9a668eba99474eebb455b744d732177130848166da1620e330dabe400c6d0
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x63A 2660 bytes
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
42c3f4df375ff6f58ff655cc4f88b5cc28f0dd33b978390db3538684a6219b74
deobfuscated-js string-concatenation normalized Acrobat API aliases at offset 0x63A 126 bytes
objstm_0023_00.bin
e8bfe65c34a535b0837ce7c541e45b42ab61e1ff13de05788daf7770f9a1ec0e
pdf-objstm-decoded PDF /ObjStm 23 0 obj (inflated) 274 bytes
polyglot_child_pdf_off000093d3.pdf
c878452f7e42b6d3cdd1721dae85835b7ddf83fc3394b778ad12863e2b52f6cf
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x93D3 43254 bytes
polyglot_child_pdf_off000124dc.pdf
0b1c923c8a0028794f3a3244dc498786746334f394e41678cc58ffbeb707d0a8
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x124DC 6125 bytes