Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecf1fdafb70bb477…

MALICIOUS

PDF

83.5 KB Created: 2021-09-23 18:10:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b45e54050e9ac2cf17ed7fb565281009 SHA-1: 836d6c4c85677b338ef684a5860e621bf5926d9d SHA-256: ecf1fdafb70bb477c8ab76c72eb90e2b6beaecc068c24b4f7df0877c407af775
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a phishing or trojan distribution attempt. The presence of numerous external URIs, many pointing to PDF files on distinct hosts, suggests a link farm designed to obscure the true malicious destination. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to trick users into downloading further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://zlato-invest.cz/upload/files/weweguvinobase.pdf In PDF document text
    • http://mwflower.com/upimagesfile///45337331772.pdfIn PDF document text
    • http://freetds.net/userfiles/file/kovobojil.pdfIn PDF document text
    • https://aymfly.com/aym_image/files/vekidenob.pdfIn PDF document text
    • http://fslawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xabebetowojul.pdfIn PDF document text
    • http://saigondome.com/uploads/userfiles/file/vazojukapazekale.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/dejizaxetafuf.pdfIn PDF document text
    • http://em-ail.ch/pictures/2/43594568560.pdfIn PDF document text
    • https://www.notusweb.com.br/ckeditor/ckfinder/userfiles/files/juvifo.pdfIn PDF document text
    • http://pizzeriagiganti.ro/imagini_ws/lezixe.pdfIn PDF document text
    • https://www.dogandemir.av.tr/paketler/ckfinder/dosyalar/files/vububekolonozoxujapotemi.pdfIn PDF document text
    • https://theipbuzz.com/images/file/xegebenatip.pdfIn PDF document text
    • https://ardiinerkh.mn/uploads/userfiles/files/nusefezodaj.pdfIn PDF document text
    • http://zamgph.com/uploads/file/190148117351.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/16478145321.pdfIn PDF document text
    • http://clean-ecology.com/Upload/files/kikijijanif.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/1265bc156a2bf4fcf663882c7a6205c3/10472506676.pdfIn PDF document text
    • http://hasomedia.com/userfiles/file/69095981812.pdfIn PDF document text
    • http://kramnyca.info/img/upload/editor/file/sejezedixeg.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/xogesigonekupolonisezopor.pdfIn PDF document text
    • http://redagowanieprac.net/Upload/file/81229602962.pdfIn PDF document text
    • http://www.madiran-cruduparadis.fr/ckfinder/userfiles/files/24401795185.pdfIn PDF document text
    • https://euronet.stonavka.cz/webpagebuilder/ckfinder/userfiles/files/76089958850.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=pokemon+mega+fire+red+download+zip+filePDF 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_off0000d888.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD888 20824 bytes
SHA-256: 77eb908a36977e8c143eece1b84097ef2cbf767f6554d1cf81c6fc51836f7f65
font_01_sfnt_off00010f4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F4B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012762.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12762 10816 bytes
SHA-256: f9ed0a56be278b8e1974aef1db749a6a74048a5d0fc994f60210ec9730bdaea4