Malicious PDF / .TXT — malware analysis report

Static analysis result for SHA-256 d7558bd779af99c7…

MALICIOUS

PDF / .TXT

1.9 KB
MD5: 9ad438be8189b2d1be568212033c99d5 SHA-1: ebcdaaa812b18cee989fb700e2f2c3e69678bef1 SHA-256: d7558bd779af99c7d968e85e04b0e8593455fdd8360061e72de9d28de9b41ff6
158 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, PDF_EVAL, and PDF_UNESCAPE. The ClamAV detection of 'Pdf.Exploit.Agent-35930' strongly suggests a known exploit. The embedded JavaScript, particularly the use of eval() and unescape(), is characteristic of obfuscated malicious code designed to download and execute further stages. The extracted file 'legacy_pdfkit_stage_000.js' likely contains the core malicious logic.

Heuristics 6

  • ClamAV: Pdf.Exploit.Agent-35930 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35930
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj111611_000.js
f23e505f155bfa9b9f356fa9fddf8d7fcafcc37fc2df3878e575e72c00c819d4
pdf-javascript-stream PDF /JS object 111611 at offset 0x666 697 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
3463e07fee345159713fe7f70a9030b44f614512b1f7e88dbe364f73a3c93a42
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2810 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).