Malicious PDF — malware analysis report

Static analysis result for SHA-256 bacf2eedde4f7e4c…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 21:02:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b948f67c0e884a25bf2a289a8649f7ee SHA-1: 086ad814c061d044f2d1c4e734834c1715f83b3d SHA-256: bacf2eedde4f7e4c6147da0ace62520f68f5f3703b9b2ae5f604fcdbd79dde11
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external resources, suggesting it functions as a downloader or redirector. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the PDF is part of a link farm designed to host malicious content. No scripts were extracted, but the PDF structure itself is used to facilitate the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 5

  • 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.
  • 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://coretry.ru/uplcv?utm_term=wear+os+download+music PDF link annotation
    • http://www.pes.edu.mn/ckfinder/userfiles/files/53022494431.pdfIn PDF document text
    • http://heorungminhphat.com/luutru/files/3068703371.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/kejibegojevuritegekevep.pdfIn PDF document text
    • http://omgmediatank.com/userfiles/files/98045288412.pdfIn PDF document text
    • http://kleinschaden-expert.de/userfiles/file/50402845347.pdfIn PDF document text
    • http://laboratorioshamalab.com/userfiles/file/fuzofuvapufuvupujasaj.pdfIn PDF document text
    • https://open-call.fr/uploaded/files/sonirexiw.pdfIn PDF document text
    • http://ecofincas.net/ckfinder/userfiles/files/duloso.pdfIn PDF document text
    • http://progettogeometra.it/userfiles/files/fuzekasatojopod.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/44083972950.pdfIn PDF document text
    • https://odontologosmalca.com/images/userfiles/file/93969296931.pdfIn PDF document text
    • http://tridiart.cl/ckfinder/userfiles/files/28193331648.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/gitopivaboxuremina.pdfIn PDF document text
    • https://dukra.sk/editor_uploads/files/jafikijofudag.pdfIn PDF document text
    • http://waterlootour.com/FileData/ckfinder/files/20210905_A2AC957CE20CFB8F.pdfIn PDF document text
    • http://htwy.com/upload/file/bilozijodosatenimuwaju.pdfIn PDF document text
    • http://conomiya.com/images/uploadedimages/file/68344367372.pdfIn PDF document text
    • http://huerural.com/uploads/image/files/giragubegezinazi.pdfIn PDF document text
    • http://capthepcongtrinh.com/uploads/news/files/53390160448.pdfIn PDF document text
    • http://logenamerica.com/userfiles/file/27212951015.pdfIn PDF document text
    • http://npxbyy.com/wang3_3_10_27/Upload/Upload/file/2021911109142487.pdfIn PDF document text
    • https://gberwanda.com/gbe/useruploads/blogs/files/pogilenujizazanurojuzu.pdfIn PDF document text
    • http://abwessex.com/uploads/files/muliludulu.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/95899044422.pdfIn PDF document text
    • https://calson.garment-pro.com/ckfinder/userfiles/files/99439055140.pdfIn PDF document text
    • https://sammycar.ch/sammy/sites/default/sammyfiles/newsletterfile/viwot.pdfIn PDF document text
    • 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_off0000d990.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD990 10612 bytes
SHA-256: 9a9e79912644483fd34f23154e0157e6ca1a27a58fa0e9e6caa60a2c9fe3c905
font_01_sfnt_off0000f1cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1CF 17468 bytes
SHA-256: b5c7d243ceae464ed45f13e54236ec8fabf85367f29fde67dd51f18f48ff9b00
font_02_sfnt_off00011f27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1