Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ffd1335a50dbcfa…

MALICIOUS

PDF

54.1 KB
MD5: 509621aa02754e9f9b59963b6927723d SHA-1: 35ae7fd14d3784348df463dc56e55364ab8df3c8 SHA-256: 8ffd1335a50dbcfa2785216fc092b0a47edc56ee8ac73d7292a16ac7642afa5f
138 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious Link

The PDF file contains XFA form elements with embedded JavaScript that utilizes a heap spray technique, indicating an attempt to exploit a vulnerability. The script decodes a string which reconstructs the URL 'http://oz9n7q.ru:8585/icon_wink.php?promos=42&ratings=151&exe=424&bugs=435'. This URL is likely used to download and execute a second-stage payload. The presence of XFA heap spray and embedded script strongly suggests malicious intent.

Heuristics 6

  • XFA form contains risky executable script high CVE related PDF_XFA_SCRIPT
    PDF embeds an XFA form whose script block contains exploit, submission/launch, or shell-execution primitives. Ordinary LiveCycle print/update scripts are left as generic XFA/JS signals unless stronger behavior is present.
  • XFA JavaScript heap-spray exploit code critical PDF_XFA_HEAP_SPRAY
    PDF contains XFA script content with heap-spray or shellcode-like JavaScript markers such as large encoded word sequences, util.pack, large arrays, or spray variable names. This is a weaponised Adobe Reader exploit pattern, not a normal interactive form.
  • Embedded script payload in PDF stream medium PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_000_off0000186d.js
26f8156313aae94a09ec84baf1196503142239943be75823c9a3d0c2c496caae
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x186D 169180 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).