Malicious PDF — malware analysis report

Static analysis result for SHA-256 43eccc865dd616b4…

MALICIOUS

PDF

87.1 KB Created: 2021-09-18 02:53:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1fe58f36f9cc0ca94b56b8ce346447db SHA-1: e7fd451363c9bf03e807bd93080c8fd35e4c5c3c SHA-256: 43eccc865dd616b4bd19edfa87a459ec3a393dee5058c527ccdefd15e18a5f99
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was flagged by a machine learning classifier and ClamAV as malicious, with a high risk score. It contains numerous embedded URLs, many of which point to PDF files hosted on potentially disposable domains, indicating a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, suggesting the document is designed to redirect users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://f-okinawa.com/img/tmp/files/27334623624.pdf In PDF document text
    • http://farmandari-sarvestan.ir/images/news/files/52182299853.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/81842203191.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131c7a266c50---56827086169.pdfIn PDF document text
    • http://stoewebdesign.no/userfiles/file/xujonu.pdfIn PDF document text
    • http://greece-ex.com/images/blog/file/99974528020.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/2021932014355364.pdfIn PDF document text
    • http://abwingsmd.com/uploads/files/46315448778.pdfIn PDF document text
    • http://www.xzass.org/ckfinder/userfiles/files/81738605500.pdfIn PDF document text
    • https://nepalipublisher.com/ckfinder/userfiles/files/90675899380.pdfIn PDF document text
    • http://siamsnail.com/media/userfiles/files/31728380994.pdfIn PDF document text
    • http://verduciautodemolizioni.it/userfiles/file/87575107224.pdfIn PDF document text
    • https://ocw.tw/uploads/files/15545708074.pdfIn PDF document text
    • https://rawoctane.com/uploads/file/68468399446.pdfIn PDF document text
    • https://tyko.pl/userfiles/file/jilebitozakaxirajebagovi.pdfIn PDF document text
    • https://drproperty.in/userfiles/file/79094450241.pdfIn PDF document text
    • http://nikolalepojevic5.com/multimedia/file/duvolamajipevib.pdfIn PDF document text
    • https://stdtekstil.com/upload/ckfinder/files/bamerajifutewu.pdfIn PDF document text
    • http://xn--hh0b97d8is16e.com/userData/board/file/fafilofevirab.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/13561216183.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/b75c601f6022142576b2307eae117517/59543428040.pdfIn PDF document text
    • https://www.delaneyllc.com/ckfinder/userfiles/files/fodep.pdfIn PDF document text
    • https://stratasphere.online/userfiles/file/7841541395.pdfIn PDF document text
    • http://akiisushi.com/uploads/files/63427604565.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=how+long+can+raw+chicken+stay+outPDF 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_off0000ef18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF18 17932 bytes
SHA-256: 2f747e804480a1b7ac99fa172a95e78bb98e51d6a0706831b7f0d633cd4a7453
font_01_sfnt_off00011d10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D10 10892 bytes
SHA-256: 64a7bcdac21e8f6be661dedfca7ac9d3fdccc4fb1f97cff5ad60c18cd1aaf41a
font_02_sfnt_off0001364c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1364C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1