Malicious PDF — malware analysis report

Static analysis result for SHA-256 822a886ce3f0b346…

MALICIOUS

PDF

1.14 MB Created: 2010-05-14 03:00:34 Authoring application: Joomla! 1.5 - Open Source Content Management (via TCPDF 2.5.000_PHP4 (http://www.tcpdf.org))
MD5: 525aec1074763b2adc0adcf244a5abfd SHA-1: 2cf531f27c941f5761d080c38ecf0469e1b539b4 SHA-256: 822a886ce3f0b3469f4a741d5278140c32fb8378f7604be24759ece3d464fca6
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, indicated by heuristics like PDF_EMBEDDED_SCRIPT_PAYLOAD and ML_NYX_PDF_MALICIOUS. The script likely aims to download and execute a secondary payload, as suggested by the presence of eval() and unescape() calls. The overall intent appears to be malicious exploitation, with the initial access vector likely being spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 5

  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits
  • 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.
  • 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://ns.adobe.com/xap/1.0/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/photoshop/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/tiff/1.0/
    • http://ns.adobe.com/exif/1.0/
    • http://www.iec.ch
    • http://www.gnu.org/copyleft/gpl.html

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000bf61.bin
a5337ef1f5a0dfe4dc8fa6b4f3ef847a53624800b5928a0eeef5b888ceecaabc
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xBF61 264072 bytes
embedded_pdf_script_0012191b.bin
0350170e872eec3a813eda3a18840fc761b1024004c758086f7148602e325af2
pdf-embedded-script PDF decompressed stream script payload at offset 0x12191B 1192461 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).