Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7e5f95ed4b07336…

MALICIOUS

PDF

72.1 KB Created: 2021-09-11 03:22:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1e4c016b10e5780189badeddb9a54447 SHA-1: 40ff5882badd0fe375aed6ce62d02b63661b880a SHA-256: b7e5f95ed4b07336921078fe0f4c91640a8aefca2ca0d18f74fd4a798d10aca3
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 embedded URLs pointing to a link farm hosted on disposable domains, a common tactic for distributing malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a deliberate attempt to obscure the final destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 http://sh-ruiyangcpa.com/userfiles/file/2021-9///20219601435541.pdf In PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135bec794272---lelojimosanenazopibuw.pdfIn PDF document text
    • http://radio6deenero.com/uploaded/files/fizulukobadamugo.pdfIn PDF document text
    • http://rcot.by/pics/files/68454720882.pdfIn PDF document text
    • https://butyfarm.mm520.net/userfiles/files/bifagodibufojogidu.pdfIn PDF document text
    • http://noithatachau.vn/webroot/img/files/47802321579.pdfIn PDF document text
    • http://hansungid.com/userfiles/file/tufopekelekejetipanu.pdfIn PDF document text
    • https://mehreganimaging.com/images/upload/files/29754539387.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/mupiwinofulanugikad.pdfIn PDF document text
    • http://usagimatur.com/files/others/kulefaxedibekenatelab.pdfIn PDF document text
    • http://orthodoxnews.us/file/78323117997.pdfIn PDF document text
    • http://baltyk.recykling-rejs.pl/imgturysta/files/pedijitisujarakod.pdfIn PDF document text
    • https://sunkamalzemecilik.com/userfiles/file/depuzozosufuvide.pdfIn PDF document text
    • http://mfo-fond.ru/ckeditor/ckfinder/userfiles/Images/files/84917470643.pdfIn PDF document text
    • http://www.sushmitamukherjee.com/fckimages/file/votige.pdfIn PDF document text
    • https://milosislandrooms.gr/userfiles/file/42392294752.pdfIn PDF document text
    • http://delta-serwis.pl/pliki/dudipagopiji.pdfIn PDF document text
    • https://5703n1n6999-6a55.com/contents/files/92086049631.pdfIn PDF document text
    • http://kingsbrite.com/kingsbrite.com/userfiles/file/dalufopifumidota.pdfIn PDF document text
    • https://chambres-hotes-aube-bleue.fr/userfiles/file/zavofesozipip.pdfIn PDF document text
    • https://www.info-service.com.tw/plugin/ckeditor/ckfinder/userfiles/files/kipokugezuxapi.pdfIn PDF document text
    • https://dennismaloney.ca/upload/editor/file/darizoxusadesel.pdfIn PDF document text
    • http://xn--80affcyoc0ac1f6a.xn--p1ai/admin/modules/ckeditor/ckfinder/userfiles/files/xazikubasilavowatijix.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/xadudufe.pdfIn PDF document text
    • http://rowadhr.com/app/webroot/upload/files/vomabelinubapulesak.pdfIn PDF document text
    • http://nhatnguyen.vn/media/ftp/file/mozidom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=subway+princess+modPDF 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_off0000b582.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB582 11048 bytes
SHA-256: e0b59c292c333e22bfa6e066c6ce2e83ea2b4aa5d7433b36255fef6f2a04721a
font_01_sfnt_off0000ceff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEFF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e711.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE711 16952 bytes
SHA-256: c2e87b93e0469cad8deedcc8cc1e99a5ad222ee73483c30cd78d8bb601de353f