Malicious PDF — malware analysis report

Static analysis result for SHA-256 138320de828a45e4…

MALICIOUS

PDF

83.4 KB Created: 2021-09-24 07:27:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 65c632b3ece94240167797b0316e0a98 SHA-1: f1210930fb62ce8183c6151e63f37a22626add42 SHA-256: 138320de828a45e48d4183a5860be3fc4edf818cea24dce390eddaf36f395e4b
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs and a heuristic firing for a link farm on disposable hosting, suggesting it's designed to redirect users to potentially harmful content. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active 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 https://ccskin.com/geektic/files/99023367112.pdf In PDF document text
    • https://joinvita.com/neu/userfiles/file/62287235093.pdfIn PDF document text
    • http://career-id.org/ckfinder/userfiles/files/45591241627.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/88460146010.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/xinigadok.pdfIn PDF document text
    • http://xn--b1adbbbaeqjtsflbfms0e.xn--p1ai/pict/file/sixenolagumodovanivubo.pdfIn PDF document text
    • https://fotoprint.lv/downloads/file/bubesotazafebuxutirowete.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/fejitujo.pdfIn PDF document text
    • https://www.jancsoalapitvany.hu/ckfinder/userfiles/files/11269943540.pdfIn PDF document text
    • http://2478.ru/admin/ckfinder/userfiles/files/komafopivun.pdfIn PDF document text
    • https://panama4d.com/contents/files/goparepomivusofatijasut.pdfIn PDF document text
    • https://mimpiindah168.com/contents/files/temotuge.pdfIn PDF document text
    • http://csc020.com/userfiles/file/20210910222051_h3jn73.pdfIn PDF document text
    • https://pelletier-tp.fr/ckfinder/userfiles/files/wonozazojibol.pdfIn PDF document text
    • https://tunguoilon.tunhua.vn/ipp/images/uploads/files/83844541529.pdfIn PDF document text
    • http://dalhousieretreat.com/cote_dor_import/admin/ckfinder/userfiles/files/bixomisurefofur.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/telovukebemaxuli.pdfIn PDF document text
    • http://interreg-ipa-husrb.com/downloads/42457516136.pdfIn PDF document text
    • http://www.lasallelille.com/admin/ckfinder/userfiles/files/77701049226.pdfIn PDF document text
    • https://cosanuesa.com/componentes/editor/ckfinder/userfiles/files/xinuvivewiguz.pdfIn PDF document text
    • https://nffcd.org/userfiles/files/jilimawurolerar.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614d41539eb09---safebedokegut.pdfIn PDF document text
    • https://gmt-tw.com/app/webroot/userfiles/files/34958372360.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/24398208394.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/mubunonusane.pdfIn PDF document text
    • https://tunhuaduytan.com/upload/userfiles/files/xonidisolazu.pdfIn PDF document text
    • https://euroquimicadistribucion.com/zabaleta/data/imagenes_contenidos/file/gobokamepisoz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=free+vpn+tomato+apkPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d85e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD85E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f070.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF070 21440 bytes
SHA-256: 0948fc606d3125565db99b0d95a8afd2d77b824df3ec6d9c21e4d99857b49170
font_02_sfnt_off00012933.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12933 10240 bytes
SHA-256: 66ca208ac4ebc9d1f0e22abace917234e78ad3c028465f5bfe9ea7e1d8e9e582