Malicious PDF — malware analysis report

Static analysis result for SHA-256 77a8de2a9bdb2803…

MALICIOUS

PDF

81.6 KB Created: 2021-09-17 21:29:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5bde26accaca88f3b8e37f90477d64a8 SHA-1: 16c173d4cafc98426e29cb5d2f842f47b0e1c6a3 SHA-256: 77a8de2a9bdb28038df6330c991f24f8d15626107c6fb54895d560dd8b4a76f6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it is designed to redirect users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://laborke.ru/uplcv?utm_term=super+bino+go+2+online+game PDF link annotation
    • http://jujucuisine.com/userfiles/file/gefudabelatipegi.pdfIn PDF document text
    • http://parejalecaros.com/adjunto/upload/fck/files/49100973861.pdfIn PDF document text
    • http://www.vinoplaza.nl/img/upload/files/32042507322.pdfIn PDF document text
    • http://1666-3668.com/attach/userfiles/file/fajusexexitukojid.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/11455882651.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/80022093254.pdfIn PDF document text
    • https://unitjaya.com/contents/files/92971589514.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/2752429958.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16144594288e2e---zexona.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/bca90a55ab6737b17c75115727eed0da/5292156834.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/wubosuxaterigidovomojefax.pdfIn PDF document text
    • http://top-rubber.com/admin/fckeditor/editor/filemanager/connectors/upload/file/sopelawojosolemitomu.pdfIn PDF document text
    • http://sergeisurzhin.ru/ckfinder/userfiles/files/guwudatuta.pdfIn PDF document text
    • http://aapltd.net/userfiles/file/wesogepulerojugu.pdfIn PDF document text
    • https://pachetedeturism.ro/images/files/65239616903.pdfIn PDF document text
    • http://tingchucontrol.com/Uploadfiles/files/92523380985.pdfIn PDF document text
    • http://www.coverseg.com/uploads/ckfinder/files/zeweziriladokawoxe.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/jebomev.pdfIn PDF document text
    • http://ventima.ru/userfiles/file/19358694082.pdfIn PDF document text
    • https://aldapa.eus/files/galeria/files/95565152681.pdfIn PDF document text
    • https://marathonlaval.com/userfiles/files/ravixusubenagawexakotozer.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/zitivelijin.pdfIn PDF document text
    • http://erex.hu/upload/file/97422895250.pdfIn PDF document text
    • https://betamachinery.sa/other_files/File/datorozi.pdfIn PDF document text
    • https://maintogelonline2.com/contents/files/27832644757.pdfIn PDF document text
    • http://ordinate-ltd.com/file_media/file_image/file/69795667144.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_off0000da9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA9D 10764 bytes
SHA-256: defe22b2a94d9e62c9f0747881d28381d75084b72e8588cdee639d0567065fbe
font_01_sfnt_off0000f321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF321 17864 bytes
SHA-256: 7b4faf546c2f6fce494781fd7c36810ea0092cd4af30e46f147c428f59b01326
font_02_sfnt_off00012136.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12136 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1