Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b79b698c3054352…

MALICIOUS

PDF

15.4 KB
MD5: 957a047bd7841147798825b29d3914c9 SHA-1: 2a0f130b25dfc6cd017460a88ca95e5b05844161 SHA-256: 7b79b698c3054352b22c78cf372368f8b7b961868031c970911cd1adc6d1a2ca
284 Risk Score

Malware Insights

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

This PDF document contains embedded JavaScript and U3D content, triggering critical heuristics related to CVE-2011-2462, a known exploit for Adobe Reader's U3D parser. The JavaScript is obfuscated but uses functions like unescape() and String.fromCharCode(), indicating an attempt to download and execute a secondary payload. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 10

  • Adobe Reader U3D parser exploit with JavaScript heap spray critical CVE likely CVE_2011_2462_U3D_HEAPSPRAY
    PDF combines U3D/3D annotation content with JavaScript heap-spray shellcode. Public CVE-2011-2462 exploit chains use a crafted U3D stream and JavaScript heap spray to control memory during Adobe Reader's U3D parser corruption.
  • U3D/3D content in PDF — Adobe Reader 3D parser CVE-family indicator high CVE related PDF_U3D_CVE_RELATED
    PDF contains U3D (Universal 3D) or 3D annotation content — CVE-2011-2462 and CVE-2009-3953 are critical vulnerabilities in Adobe Reader's U3D processing that allow arbitrary code execution. U3D content in PDFs is extremely rare in normal documents.
  • 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.
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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.
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0015_000.js
effcfd82b76643631ac810c45878e463292983350048214c3d718cff655d077f
pdf-javascript-stream PDF /JS object 15 at offset 0x7D6 11916 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 8 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
u3d_00_off000003cb.bin
db47f9e6c2fa22cca9aaaaba842bc1035f54c0acd3737dbd64b69dc1671da5eb
pdf-3d-stream PDF U3D 3D stream at offset 0x3CB 1268 bytes