Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9ccac1800dfc590…

MALICIOUS

PDF

82.2 KB Created: 2021-09-22 22:31:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e7fb36e8a1ac292f52a66570b314bbf9 SHA-1: 2a727859ee72a42fe1d5d83387d7f839eaf94ba8 SHA-256: a9ccac1800dfc590a6a6c392059c702a45350ce88aa3a7432e492b9edb993108
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm. The document body is heavily obfuscated, but the presence of numerous embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest a phishing or malware distribution attempt. No scripts were extracted, but the overall structure points to a malicious PDF designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://yuanhebiotech.com/upload/files/kavunaziwonuvedaguvodi.pdf In PDF document text
    • http://parfumerieindex.nl/images/uploads/56486038721.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/pufekefez.pdfIn PDF document text
    • http://ecolservizinettuno.com/userfiles/files/rowoxulivudozatireti.pdfIn PDF document text
    • http://xn----dtbhwhggdaoqfh3d.xn--p1ai/media/file/55529270143.pdfIn PDF document text
    • https://path.mn/userfiles/files/65292033411.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/161356c8c4971f---ruwinidorapafegatajewawas.pdfIn PDF document text
    • http://jcnjl.com/userfiles/files/57066823280.pdfIn PDF document text
    • https://rh4-h1tapi-turbo.com/contents/files/11170267159.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/1aa50ad933ec4ad15e762d90ad8c6830/dobuzarepuka.pdfIn PDF document text
    • https://atrax.eu/userfiles/file/20617416178.pdfIn PDF document text
    • http://www.kroonzuivel.nl/ckfinder/userfiles/files/tilixomasafelitobe.pdfIn PDF document text
    • https://samsunyapi.com/userfiles/files/28355013291.pdfIn PDF document text
    • http://muntepa.com/userfiles/files/wideviwinijurumesobi.pdfIn PDF document text
    • https://silverbirdmarketing.com/pages/images/file/26537169834.pdfIn PDF document text
    • http://expertworker.paraleumarian.ro/app/webroot/files/userfiles/files/levaberelimif.pdfIn PDF document text
    • http://americandeliorder.com/uploads/files/27770023245.pdfIn PDF document text
    • http://dycelife.com/userfiles/file/furubenoxuvifivupuvitago.pdfIn PDF document text
    • http://tottazo.com/userfiles/file/nowizivufozulowa.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/funamepusexukuvo.pdfIn PDF document text
    • https://impactmediaresources.com/userfiles/file/56798980791.pdfIn PDF document text
    • http://zawodydrwali.pl/app/webroot/userfiles/file/753170616.pdfIn PDF document text
    • http://navigator-nsk.ru/userfiles/file/10070735500.pdfIn PDF document text
    • https://www.dogandemir.av.tr/paketler/ckfinder/dosyalar/files/dapirorabalaguj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=online+games+like+skribblPDF 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_off0000dd1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD1F 17668 bytes
SHA-256: e7b7ef72982b7871912b638c9d4e57eb0a1f2b397bb9bd9d5a6a34244dc4875d
font_01_sfnt_off00010afc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AFC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012313.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12313 10492 bytes
SHA-256: b4cbff532e927bd8ae386a32106e3a50e19738c1a2e11f5e8ea58214ff562b1f