Malicious PDF — malware analysis report

Static analysis result for SHA-256 6242d7fb0b8a5018…

MALICIOUS

PDF

6.8 KB
MD5: 23220304eeb931243fa8fbddbf66f19a SHA-1: dc32cde1867018ab6a7b5765629b5c0f1b0a43a9 SHA-256: 6242d7fb0b8a5018e0115339a568e870bcb2d32fdb657aa61bd8446738752861
328 Risk Score

Malware Insights

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

This PDF file contains obfuscated JavaScript that leverages the CVE-2009-0658 exploit for Adobe Reader. The JavaScript is designed to execute arbitrary code, likely to download and run a secondary malicious payload. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 9

  • Adobe Reader JBIG2Decode generic heap-spray exploit critical CVE likely CVE_2009_0658_GENERIC_SPRAY
    PDF combines JBIG2Decode image streams with JavaScript heap-spray or decoder scaffolding. This is likely CVE-2009-0658-family Adobe Reader JBIG2 exploitation, but it lacks the stricter Reader-9 version gate or decoded page-word shellcode fingerprint required by the exact rule.
  • JBIG2 + active content high CVE related PDF_JBIG2_ACTIVE_CONTENT
    JBIG2Decode appears with JavaScript/XFA/RichMedia — a related indicator for JBIG2 parser-exploit families including CVE-2021-30860 and CVE-2009-0658, but not a unique CVE fingerprint.
  • 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.
  • ClamAV: Heuristics.PDF.ObfuscatedNameObject critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Heuristics.PDF.ObfuscatedNameObject
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • JBIG2Decode filter medium PDF_JBIG2
    JBIG2 image decoder present — historically used in zero-click exploits
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
53c87abfeb74503c39899313655374da6d9dbd8dc8c0a09cc7d2a8ca991cedde
pdf-javascript-stream PDF /JS object 6 at offset 0x212 5272 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s).