Malicious PDF — malware analysis report

Static analysis result for SHA-256 631c3c46dc03fb47…

MALICIOUS

PDF

793.7 KB Created: 2010-09-16 21:45:23 Authoring application: Joomla! 1.5 - Open Source Content Management (via TCPDF 2.5.000_PHP4 (http://www.tcpdf.org))
MD5: 7c1735e02f988e474ef53f5c7c3242fa SHA-1: afa32546351ff182547dbf7b107c9cfe2022beed SHA-256: 631c3c46dc03fb47dc6d50b86be841d9c4fe97a96fb1fdd353e5a815dc3c44c3
132 Risk Score

Malware Insights

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

The PDF contains a hidden HTML iframe and was flagged by a machine learning classifier and ClamAV as malicious (Html.Spyware.IMG-7). This suggests the document is designed to exploit vulnerabilities in PDF viewers to download and execute a second-stage payload from the unknown URL http://www.codeforum.cn/free/max1.htm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9859

Heuristics 3

  • ClamAV: Html.Spyware.IMG-7 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Html.Spyware.IMG-7
  • PDF contains hidden external HTML iframe high PDF_HIDDEN_HTML_IFRAME
    PDF bytes contain a hidden zero-size HTML iframe pointing to an external HTTP(S) URL. This is a strong malicious dropper/redirect indicator and is not expected in ordinary PDF content.
  • 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://www.codeforum.cn/free/max1.htm
    • http://ns.adobe.com/xap/1.0/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/iX/1.0/
    • http://ns.adobe.com/exif/1.0/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/photoshop/1.0/
    • http://ns.adobe.com/tiff/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://purl.org/dc/elements/1.1/
    • http://www.iec.ch
    • http://www.gnu.org/copyleft/gpl.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000cec8.bin
a5337ef1f5a0dfe4dc8fa6b4f3ef847a53624800b5928a0eeef5b888ceecaabc
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xCEC8 264072 bytes