Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc3b17c9f81e7117…

MALICIOUS

PDF

80.5 KB Created: 2021-09-12 16:19:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 877360ed50c922e09108cbf69ba117c9 SHA-1: 984e8af8a2578ff2e9123dd5d1fadee673a03d97 SHA-256: bc3b17c9f81e71171eb84bcce509d143c50a072a0c15e434624fd76d987ecd52
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm on disposable hosting. The presence of numerous embedded URLs, many pointing to suspicious domains, supports a phishing or redirection attack. While no scripts were explicitly extracted, the PDF format itself can embed JavaScript for malicious actions, hence the T1059.007 technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nstoplana.rs/ckfinder/userfiles/files/juwonixomovulomuwirapero.pdf In PDF document text
    • https://pinkrali.com/calisma2/files/uploads/nevuvewopixanupuvum.pdfIn PDF document text
    • http://roomyab.ir/basefile/roomyabir/files/96548013571.pdfIn PDF document text
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/ketojigemo.pdfIn PDF document text
    • http://sk-uralstroy.ru/uploads/files/rigotitewedaxo.pdfIn PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/migilevefagat.pdfIn PDF document text
    • http://bouwbedrijfbouwheer.nl/userfiles/file/82999571429.pdfIn PDF document text
    • http://china-miyaco.com/img/file/2021911195722.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613de57b80fa9---3008903382.pdfIn PDF document text
    • https://artistprasanna.com/userfiles/file/wovararezilevuxew.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/zetamiwiponebe.pdfIn PDF document text
    • http://karthikeyanjayaram.in/userfiles/file/wipukegonikiwusaroboxakiw.pdfIn PDF document text
    • https://bbox.ru/images/shared/file/mutaputuradikogopifem.pdfIn PDF document text
    • http://mimarkamilozkartal.com/userfiles/files/mumugimemavugejokarugowe.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/87101662596.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/35518791413.pdfIn PDF document text
    • https://nitdgp.ac.in/uploads/userfiles/files/98518182916.pdfIn PDF document text
    • http://thanglong.vn-greenenergy.com/ckfinder/userfiles/files/rameru.pdfIn PDF document text
    • http://jandenzobv.com/image_uploads/file/biwerutatojid.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/445a4a8225f844378003d02502ec6d9d/25532052490.pdfIn PDF document text
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/65756013505.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/58150206653.pdfIn PDF document text
    • http://travelsi.ru/ckfinder/userfiles/files/podupomebibenufedegidexu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=get+ios+on+androidPDF 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_off0000d71d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD71D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2F 17888 bytes
SHA-256: e54e76fb1edd9f8438b4fc69c8f13a3a6a3c6cfd6a11a99ca89790056881cb05
font_02_sfnt_off00011d71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D71 10236 bytes
SHA-256: 6e627398d9e43a0a89ebdacdfc6aff8e8697301a1fcdc92c5851660f1f54c72e