Malicious PDF — malware analysis report

Static analysis result for SHA-256 67fc5abf29bb08cd…

MALICIOUS

PDF

45.4 KB
MD5: 35e8a82fd60f87c4374fa749b4b90eea SHA-1: e3e590e91b021af7c8290b6dbae947a74847e602 SHA-256: 67fc5abf29bb08cdc30f6bdb87fde555cb3e479877977c751cb81d621d29ce8e
170 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is heavily obfuscated and utilizes a custom Base64 decoder. This script exploits CVE-2009-0927 in Adobe Reader, leading to the execution of shellcode. The shellcode, in turn, contains a URL used to download a second-stage payload. The primary purpose appears to be exploiting the reader to download and execute further malicious content.

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://tingv.ru/fm5ruk4llLNoeI1UkFtBgCfeKz826aua?p=1&s=oldpdf

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0008_000.js
a588178576a05db8c3b130243c66bbb41f86d006b751bab3dd0d05e7db75d75e
pdf-javascript-stream PDF /JS object 8 at offset 0x1D3 9143 bytes
custom_b64_stage_000.js
98f7c5755251eaae25166379f09dd8f197142545edf7b19e10c43a2989ce1693
deobfuscated-js custom Base64 decoded JavaScript layer 2 (PDF /JS object 8) at offset 0x8A7 1499 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).