Malicious PDF — malware analysis report

Static analysis result for SHA-256 316084f5d9b71484…

MALICIOUS

PDF

81.8 KB Created: 2021-10-06 02:44:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e80053cc4317a387fbbbe94ae54e04a6 SHA-1: 6f24c8580e6f62ddc16d2c0b36d4c0765eaf098c SHA-256: 316084f5d9b71484e3aa1af50ec88c621c5197bfcd28a909abb363cf14191356
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier with high confidence. It contains numerous embedded URLs, many of which point to disposable hosting and are structured as link farms, suggesting a phishing or malware distribution scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true malicious destination. No scripts were extracted, but the presence of external URIs and the link farm structure strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://queure.ru/uplcv?utm_term=my+puppy+sleeps+with+his+eyes+open PDF link annotation
    • http://xz-brand.com/ckfinder/userfiles/files/8629319906.pdfIn PDF document text
    • http://1-sanya.com/blog_images/blog_/file/fubeburogajeso.pdfIn PDF document text
    • http://matrixpaint.com/ckfinder/userfiles/files/38518749687.pdfIn PDF document text
    • https://matratva.in/userfiles/file/63403838604.pdfIn PDF document text
    • https://detectagsafety.com/ckfinder/userfiles/files/69985954919.pdfIn PDF document text
    • http://divelife.kz/files/file/rogukovomap.pdfIn PDF document text
    • https://santaclara.com/wysiwygfiles/file/nizabi.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/4ea1a1784f256a817c87068d9d8e6fa2/vamoxesoxurarazusup.pdfIn PDF document text
    • http://www.programasaudetotal.com/arquivos/file/gibomagezovizuselusov.pdfIn PDF document text
    • https://www.singaporemedicalclinic.com/ckfinder/userfiles/files/52790835741.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/mefupetajurimonefumika.pdfIn PDF document text
    • http://romento.com/uploaded_files/userfiles/files/rekerasejinewesad.pdfIn PDF document text
    • https://horacebatten.com/ckfinder/userfiles/files/xotomeja.pdfIn PDF document text
    • http://jun-travel.com/userfiles/file/fizamixag.pdfIn PDF document text
    • http://www.satunatc.ac.th/ckfinder/userfiles/files/44296072856.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16142594f1ce3f---lunowifitenujojo.pdfIn PDF document text
    • https://kga-am-adlergestell-ev.de/kga/ckfinder/userfiles/files/butewapoxaloxexiwu.pdfIn PDF document text
    • https://hnhaa.com/userfiles/tnejp/files/dojuriwosoxiru.pdfIn PDF document text
    • https://www.indoorclub-informa.com/boletines/img/file/kukizunakasopuvi.pdfIn PDF document text
    • http://print-resource.co.uk/ckfinder/userfiles/files/kepolaretamakudako.pdfIn PDF document text
    • http://pnlestari.com/visitbali/image/files/68221870796.pdfIn PDF document text
    • http://saraiaser.nl/userfiles/file/70446988934.pdfIn PDF document text
    • https://swiz.eu/files/editor/nelapib.pdfIn PDF document text
    • https://hantverkarenisandby.se/UserFiles/files/jijot.pdfIn PDF document text
    • http://amsaneeraus.fi/userfiles/files/36072038442.pdfIn PDF document text
    • http://vatlieulamnha.com/media/ftp/file/83086251928.pdfIn PDF document text
    • https://plasy.com/uploads/file/pipaz.pdfIn PDF document text
    • http://heizler.hu/files/file/majofunevetafafupakasug.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_off0000dd2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD2C 10380 bytes
SHA-256: 0f51db39454fbf9b5222144f102a29eb3a35ef1cda9af3a497ae0ac8562cd78c
font_01_sfnt_off0000f4ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010cc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CC0 17348 bytes
SHA-256: 0966b53044cdf3de5b21c1861c893065bf61b39c2471fce409157dddd72418b6