Malicious PDF — malware analysis report

Static analysis result for SHA-256 efb25132b927b546…

MALICIOUS

PDF

78.6 KB Created: 2021-10-05 18:33:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: bd78bda9912bf8a81d4d721a226f1ec4 SHA-1: d853d404d215de193086cda9025c83ecd5ee6e0d SHA-256: efb25132b927b54646c823ad9037fc270d93d9f9ac049b975a9bcf149991b638
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The presence of these links and the overall structure strongly suggest an attempt to lure users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • 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 http://innovad-ltd.com/userfiles/file/luzezagarakurim.pdf In PDF document text
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147a7a336fdd---lomovexazuxonako.pdfIn PDF document text
    • http://uni-farm.pl/ckfinder/userfiles/files/13657328024.pdfIn PDF document text
    • http://dejede.com/userfiles/file/wewutudanek.pdfIn PDF document text
    • https://kolkatanagariksammelan.org/ckfinder/userfiles/files/95150517990.pdfIn PDF document text
    • http://dfwarbitrator.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/59988261469.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614d875ce983b---movuwofigo.pdfIn PDF document text
    • http://hijoin.hu/editor_up/40088453488.pdfIn PDF document text
    • http://marisqueandopremios.com/campannas/file/wuvefelefope.pdfIn PDF document text
    • http://dellalontra.it/userfiles/files/bosuxikurorapamuke.pdfIn PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/danovimixir.pdfIn PDF document text
    • http://grandfiltr.com/files/file/rilodarumapanozawifopej.pdfIn PDF document text
    • http://darstin.com/userfiles/files/xeguligimurada.pdfIn PDF document text
    • https://heritagecambodiatravel.com/userfiles/file/67354430506.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/4441e0027388aefa7017a5ef9be35d90/31534775074.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/82fdcee049e122d895c61323bb02d140/7944899707.pdfIn PDF document text
    • https://kingdom.vn/userfiles/file/dafebopimonugodixex.pdfIn PDF document text
    • https://mmrh.myagenda.cz/pictures/editor/files/1017401392.pdfIn PDF document text
    • https://yptea.com/data/fckeditor/files/13267550007.pdfIn PDF document text
    • http://prosefkuchare.cz/userfiles/14542119865.pdfIn PDF document text
    • http://ordineveterinarivenezia.eu/userfiles/files/kamapuvepaxox.pdfIn PDF document text
    • http://lifecare4all.com/upload/files/86794895532.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=convert+pdf+to+exe+onlinePDF 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_off0000cdce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDCE 10360 bytes
SHA-256: fdb5c6cf3a8e3feb04c84022621b1b7b2d4ea726987e528b110e15f30019f235
font_01_sfnt_off0000e550.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE550 18268 bytes
SHA-256: 2b06f8b3dd11c1d53550066524ce0ce7c24a5151d97905c50db139b5548656ae
font_02_sfnt_off000114a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1