Malicious PDF — malware analysis report

Static analysis result for SHA-256 63875ebf73254258…

MALICIOUS

PDF

83.4 KB Created: 2021-10-06 11:27:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5f55b3f1bb1451fb30ae507a43775c22 SHA-1: ff022eeb2f23f0e09e6a9127df4d253282beac7c SHA-256: 63875ebf73254258ece320eb808d9491e27bb60ceb127bef29efb2a8f0836379
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Numerous external URIs were extracted, indicating a link farm designed to redirect users to potentially malicious content. The PDF structure and embedded links strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://cructi.ru/uplcv?utm_term=the+impossible+whopper PDF link annotation
    • http://miwon.com.vn/app/webroot/uploads/files/nabew.pdfIn PDF document text
    • https://akanaymatbaa.com/calisma2/files/uploads/tewamoloxuxep.pdfIn PDF document text
    • https://jokerprod.net/userfiles/file/10434016080.pdfIn PDF document text
    • http://dytac.hk/userfiles/6567008158.pdfIn PDF document text
    • http://ukonlinedirect.com/userfiles/files/kigiwegijuzetut.pdfIn PDF document text
    • https://kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/76515726440.pdfIn PDF document text
    • http://sallytour.com/FileData/ckfinder/files/20211003_33B845B3D30037AD.pdfIn PDF document text
    • http://ohappy.org/userData/board/file/81214030814.pdfIn PDF document text
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/laminuwer.pdfIn PDF document text
    • http://ylpcl.com/ckfinder/userfiles/files/gufitovoxubuwibelamumewef.pdfIn PDF document text
    • https://pasifikendustriyel.com/userfiles/file/44807474542.pdfIn PDF document text
    • https://abisspaandboutique.com/nbloom/fckuploads/file/71103376731.pdfIn PDF document text
    • http://olivetheater.com/userData/board/file/52407480007.pdfIn PDF document text
    • https://nocnepal.org.np/ckfinder/userfiles/files/pilevuzezofupegiwujogub.pdfIn PDF document text
    • http://www.vegagastro.pl/upload/file/kubox.pdfIn PDF document text
    • https://noithathoaphat11.com/upload/files/dajonuzasuv.pdfIn PDF document text
    • http://thestarbusan.com/FileData/ckfinder/files/20210923_8723E4723D2B04BB.pdfIn PDF document text
    • http://www.huntsvillepr.com/files/files/9415219658.pdfIn PDF document text
    • http://ggbris.com/slbdavbatala/userfiles/file/14564408031.pdfIn PDF document text
    • https://nieruchomosciturystyczne.eu/files/file/fefod.pdfIn PDF document text
    • https://zlatartopalovic.rs/files/rizavese.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d7ac37c961---1099971307.pdfIn PDF document text
    • http://life-homeshop.com/asset/uploads/files/49152658531.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210916233045.pdfIn PDF document text
    • https://ketdoanbus.com/webroot/img/files/ganerivutamefar.pdfIn PDF document text
    • http://safiorida.nl/operatori/userfiles/file/39388745004.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_off0000ddd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD5 10344 bytes
SHA-256: 954d1374ace002651e97c61d5e17fac8675c13dcfe5be53b6c91d534fa235217
font_01_sfnt_off0000f4f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D05 19380 bytes
SHA-256: 18a1ed5b29629cc67400b0f4dc1e1cb20119d88409d7a89549cff2013a987e67