Malicious PDF — malware analysis report

Static analysis result for SHA-256 8251c2b4ff4d7f82…

MALICIOUS

PDF

70.0 KB Created: 2021-09-12 17:15:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 419e291344d27d9afb465d79a0809e7c SHA-1: 0d1223191c8612116a8d59af7c8cad47a13b9859 SHA-256: 8251c2b4ff4d7f82742b9873f3ba66f99297c6f97ff978a37e416a0307a316c1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the presence of PDF_ACROFORM_BUTTON and PDF_URI heuristics points to interactive elements designed to redirect users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • 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://fotografoenricogiampieri.it/userfiles/files/wopexegevubexusi.pdf In PDF document text
    • http://bright-mineral.com/uploadfile/file/2021091008251128.pdfIn PDF document text
    • http://kondicionery-noginsk.ru/upload_picture/file/96337045272.pdfIn PDF document text
    • http://goldenteriyaki.com/uploads/files/kudonetexetamakivelaxilo.pdfIn PDF document text
    • https://tidurmalam2.com/contents/files/20873560889.pdfIn PDF document text
    • https://k85shj16h-561lt.com/contents/files/dusosomoxorokavolevurudi.pdfIn PDF document text
    • https://worldpigment.com/image/upload/File/70711344138.pdfIn PDF document text
    • http://lachambredechos.com/userfiles/file/23709558366.pdfIn PDF document text
    • http://olddieselparts.com/ckfinder/userfiles/files/feveluzoworozevifo.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/0gtkslqnb4mjj58sk7qqujp8p5/rokosonikaxizatez.pdfIn PDF document text
    • https://lecachet.fr/docs/files/14993551582.pdfIn PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/59713023135.pdfIn PDF document text
    • http://spbmedax.ru/sites/default/files/uploads/tojozilibubetugebepuboba.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613af85388492---jododezu.pdfIn PDF document text
    • http://ruizhishengwu.com/uploadfiles/file/041327095684.pdfIn PDF document text
    • http://miskolciharsona.hu/pictures/file/40681400426.pdfIn PDF document text
    • http://xsjsbzrw.com/uploads/files/zomolafu.pdfIn PDF document text
    • https://rtquery.reitoken.org/Coaching123/images/files/vufiteraxatuwevibolif.pdfIn PDF document text
    • http://lnimeina.it/userfiles/files/46389450233.pdfIn PDF document text
    • http://krajinar.cz/soubory/files/23075397328.pdfIn PDF document text
    • http://exosportsante.fr/ckfinder/userfiles/files/waninevakelodeboruxilutop.pdfIn PDF document text
    • http://geometrarontani.it/userfiles/files/xufazidisaduwizox.pdfIn PDF document text
    • http://simsvizag.com/contentimages/file/71884439109.pdfIn PDF document text
    • https://noithatkuongthinh.com/uploads/files/98925151389.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=big+games+for+android+free+downloadPDF 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_off0000b39b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB39B 10740 bytes
SHA-256: 685b36f26611c601883f952104c5045e40cfc6d29bee469b03ea3d1c4bf77c84
font_01_sfnt_off0000cc1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC1E 15128 bytes
SHA-256: 9e6ace983162fe3aceca6b7b6642938f947d65d76d1cd0b96c167df95d238187
font_02_sfnt_off0000f264.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF264 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1