Malicious PDF — malware analysis report

Static analysis result for SHA-256 648e8c6e818ba92d…

MALICIOUS

PDF

45.6 KB
MD5: 2911d7da3532bc9b2fee2147ac2dee53 SHA-1: f3abd360cfc1b201c54449188ab6ed84e3be41f5 SHA-256: 648e8c6e818ba92d1ef64c0fd13cb14b7eaff479ee7520184c5375ba806f1d77
170 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that exploits CVE-2009-0927 using the Collab.getIcon method. This script is obfuscated and attempts to download a second-stage payload from the URL http://rnpo.ru/ItuBF21PNxyDGU84axtoFdbr84x4Dmbc?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://rnpo.ru/ItuBF21PNxyDGU84axtoFdbr84x4Dmbc?p=1&x=945&s=oldpdf

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0008_000.js
4c102542901c05fc9be50376c94efac030772cb534fcea9533599dfb0f9ac34a
pdf-javascript-stream PDF /JS object 8 at offset 0x1D3 9187 bytes
custom_b64_stage_000.js
c9daf420056207c4a1a02f4df4a25cd3cb84786dd53c51a408c885611c6312c2
deobfuscated-js custom Base64 decoded JavaScript layer 2 (PDF /JS object 8) at offset 0x8A7 1511 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).