Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a6725f034f6e7e3…

MALICIOUS

PDF

45.8 KB
MD5: 1b50a31a660d229be557da050247cf2c SHA-1: 0e16a5057f0332c8577db50af46dd0d8859002f0 SHA-256: 0a6725f034f6e7e3c087aec23fb08a538ea1067a73715da005f918ec13a010ca
170 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF file contains embedded JavaScript that exploits CVE-2009-0927 in Adobe Reader. The script is heavily obfuscated but ultimately decodes a URL from which it downloads and executes a second-stage payload. The reconstructed URL is http://wholv.ru/gpjycb1S0lnnL0sXuXiuIRgCD0yG68Mc?p=1&x=945&s=oldpdf. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 7

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
  • PDF JavaScript shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF JavaScript shellcode contains a hardcoded http(s) URL stored as little-endian %uXXXX Unicode escapes. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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.
  • 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.
  • Suspicious extracted artifact info 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 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://wholv.ru/gpjycb1S0lnnL0sXuXiuIRgCD0yG68Mc?p=1&x=945&s=oldpdf

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0008_000.js
a681ff7751a8bc7e0bdcb8c3499e316d4a265e636a89422feb5279e288fc0986
pdf-javascript-stream PDF /JS object 8 at offset 0x1D3 9215 bytes
custom_b64_stage_000.js
4b43da2549bdc364031a25f21b25116c7cd82a9b4cb35c7c07641a6481723357
deobfuscated-js custom Base64 decoded JavaScript layer 2 (PDF /JS object 8) at offset 0x8A7 1517 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).