Malicious PDF — malware analysis report

Static analysis result for SHA-256 391bb17c1013ffe2…

MALICIOUS

PDF

82.7 KB Created: 2021-09-17 13:03:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f3679a9b55f28099f8a4d48d2637ec90 SHA-1: 0355f323c1bfc3929a23a6c644ae08459a73ff6e SHA-256: 391bb17c1013ffe2476331ab0b39e3175a86b00beae9aa45c98b467315c59e42
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and is identified as a link farm hosted on disposable domains, indicating a likely attempt to redirect users to malicious content. Although no scripts were explicitly extracted, the nature of the PDF and its embedded links strongly suggests it is designed to facilitate malicious web traffic, potentially for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://inwebjor.ru/uplcv?utm_term=a+flat+major+guitar+chord PDF link annotation
    • http://farmina.ru/uploads/files/72602572690.pdfIn PDF document text
    • http://contextuae.com/resimler/files/50996725700.pdfIn PDF document text
    • http://calisnt.com/uploads/files/23618928773.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/92551271798.pdfIn PDF document text
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/xibiwadovupawakosuwok.pdfIn PDF document text
    • http://manvilastrust-org.bvirani.com/ckfinder/userfiles/files/sojagulepa.pdfIn PDF document text
    • https://podereilmontaleo.it/writable/public/userfiles/file/33074601755.pdfIn PDF document text
    • http://sindikat777.ru/ckeditor/ckfinder/core/connector/php/uploads/files/17130605799.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/vnegrff36a617n1glp0b8jv3ph/23855856584.pdfIn PDF document text
    • http://www.sictombbi.fr/ckfinder/userfiles/files/7249313011.pdfIn PDF document text
    • http://psychologkmalinowska.pl/ckfinder/userfiles/files/muxumutegusanamebob.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021090805474166.pdfIn PDF document text
    • http://adamslakeband.org/userfiles/file/57370138839.pdfIn PDF document text
    • https://hse.tw/upload/file/66548564532.pdfIn PDF document text
    • http://abwclayton.com/uploads/files/90361083232.pdfIn PDF document text
    • https://cvzona.lt/resources/img/files/99408857921.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/c8fbcbe3a221d53898bb243f83caf0ed/kukolegadoxivamekalabades.pdfIn PDF document text
    • http://domesticsolutionsagency.com/userfiles/file/13219094894.pdfIn PDF document text
    • https://cometsecurity.in/admin/userfiles/file/dijuralomomosuw.pdfIn PDF document text
    • http://acupunctuuryao.nl/ckfinder/userfiles/files/lanijoxoxikozututikadu.pdfIn PDF document text
    • https://okazdedziecko.pl/_files/Media/file/penemujogoditomuf.pdfIn PDF document text
    • http://zoop-tech.com/ckfinder/userfiles/files/loranet.pdfIn PDF document text
    • https://hotelangela.hu/userfiles/file/67134333099.pdfIn PDF document text
    • http://gibkrakow.pl/uploads/files/dolobateza.pdfIn PDF document text
    • https://inprovitmexico.com/ckfinder/userfiles/files/42013846476.pdfIn PDF document text
    • http://karimeh.com/public/userfiles/file/tenotebototakude.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_off0000dafa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAFA 10728 bytes
SHA-256: 5d4805648247ee2ccca0a62624c72815a0544995f5eb47a51487a8b1739f578c
font_01_sfnt_off0000f360.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF360 19320 bytes
SHA-256: 67e693b064546f2f6126ca5d716923dafa0e73727cbce246720d288f49417277
font_02_sfnt_off000124ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1