Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2c114f6656867c5…

MALICIOUS

PDF

80.2 KB Created: 2021-09-19 02:03:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 574447958db0d98d730f0639b08db926 SHA-1: 1976d418d2932780d7a164ddcbc10b3b3c9acfc7 SHA-256: a2c114f6656867c58e8711e87a873309d718e6ad9c03635e9d1e794d1d99dd15
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier. It contains embedded JavaScript and numerous external URIs, including one pointing to 'inwebjor.ru' with a 'free robux' lure. The PDF structure suggests it acts as a link farm, directing users to potentially malicious external sites, which is consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://inwebjor.ru/uplcv?utm_term=free+robux+codes+2020+may PDF link annotation
    • http://www.alexgis.com/siteuploads/editorimg/file/soluleboru.pdfIn PDF document text
    • http://ferrocom-spb.ru/userfiles/files/11256989031.pdfIn PDF document text
    • http://koala-al.com/d/files/nunepidaxapusesefilinop.pdfIn PDF document text
    • https://cpsguffanti.it/uploads/file/12775918017.pdfIn PDF document text
    • http://taikenplan.jp/ckfinder/userfiles/files/gigenomujupepumidenafev.pdfIn PDF document text
    • http://maradonasalud.com.ar/ckeditor/ckfinder/userfiles/files/dixevanitiwod.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/4ur9hj8fbpqd0h0dl9kjfh5tu8/43004570426.pdfIn PDF document text
    • http://denetimmusavirlik.com/userfiles/file/29560583593.pdfIn PDF document text
    • http://wdnederland.nl/file/37387375858.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/juzajag.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/bumezejajenolekutimojo.pdfIn PDF document text
    • http://heureka-cz.eu/files/nagapowebadaja.pdfIn PDF document text
    • https://pleasanton.com/wysiwygfiles/file/rufibelirapopomuti.pdfIn PDF document text
    • http://sictombbi.fr/ckfinder/userfiles/files/11495425920.pdfIn PDF document text
    • http://www.wcd.com.tw/ezadmin/ckfinder/userfiles/files/zadafitasebom.pdfIn PDF document text
    • https://pergamine.com/ckfinder/userfiles/files/zudilokozavekojufogiruge.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613176e52584e---9154036477.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/93816705775.pdfIn PDF document text
    • http://hide-bo.com/img/tmp/file/mumojezepivosoto.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/90641421503.pdfIn PDF document text
    • https://kaemsp.org/upload/editor/file/27368613350.pdfIn PDF document text
    • http://ikuma-car.com/js/upload/files/62108774605.pdfIn PDF document text
    • https://www.aicsmindia.org/ckfinder/userfiles/files/59080726202.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/fajulatonofagisotalival.pdfIn PDF document text
    • http://cargologicru.com/sadm_files/jigijilupituvadinuxota.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210917025031.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_off0000d574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD574 17184 bytes
SHA-256: ebe8a0f9ce510552bba06056780266a7195f7370548c7b1d5d07f6d136eaef85
font_01_sfnt_off0001022f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A46 10864 bytes
SHA-256: 19dc951b65b79e2c4353c95db02117ae6eb76a2a4e1137b5186098c16f13a426