Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2a53eb1f08f3543…

MALICIOUS

PDF

80.4 KB Created: 2021-09-15 16:10:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b034f226efa3dcc4cba0e9f71684a140 SHA-1: e571539b1785dd0e58ec814d94fbc9d4b13e3762 SHA-256: a2a53eb1f08f35436507fab0b9aafeb4941c55de9640e9ca1c847d0d9056aca2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous external links, many pointing to unknown PDF files, suggests a link farm designed to distribute malicious content or phish for information. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, identifying the document as a link farm on disposable hosting.

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 http://bbmeti.it/userfiles/files/96118873646.pdf In PDF document text
    • http://svsteinfurth.de/radsportfiles/file/97110486876.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/42056968952.pdfIn PDF document text
    • http://pdww.ru/ckfinder/userfiles/files/sidutubasosajedubefozi.pdfIn PDF document text
    • https://arerp.kr/data/file///nadusuwadalewolobulikaj.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/rawagodepavavitujo.pdfIn PDF document text
    • http://workontext.ru/media/file/94031959668.pdfIn PDF document text
    • http://www.mattig-accounting.bg/fisiere/file/litopelalameset.pdfIn PDF document text
    • http://citysoupsbellevue.com/uploads/files/filovunipijededela.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1613d26e71e65c---xelebokuzezisixuxonisa.pdfIn PDF document text
    • http://hillsclinic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/femewowolenefew.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/49447986452.pdfIn PDF document text
    • https://trsoftyazilim.com/genelresimler/file/36262584006.pdfIn PDF document text
    • http://lnhaihui.com/userfiles/file/20210914002225_355513335.pdfIn PDF document text
    • https://pensiunea-escape.ro/ckfinder/userfiles/files/dexudunejeleguxusajediza.pdfIn PDF document text
    • http://usatovl.ru/upload/fckeditorfile/17498239190.pdfIn PDF document text
    • https://ezokniga.com/uploads/file/kawexiguwijanubowazof.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614014a132a7d---lanofukubu.pdfIn PDF document text
    • http://viettelhaiphong.me/data/dulieu/files/nifakuxipavikug.pdfIn PDF document text
    • http://thuexedanang247.com/uploads/image/files/piwuteruvazoseni.pdfIn PDF document text
    • http://werder-ritter.de/UserFiles/File/kikekupufefubetofojufeb.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/dipijetopud.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/64723075327.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210906085234735.pdfIn PDF document text
    • https://ww150004.linebot.net/upfile/files/20210914160736.pdfIn PDF document text
    • http://moscowfashion.net/content/xuploadimages/file/16335845299.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=popular+ringtones+for+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_off0000d5cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5CC 10772 bytes
SHA-256: 743b7a3a64a08179be9cc1e1105d5a42293d1b0a5d77003e9af620cd043e534e
font_01_sfnt_off0000ee8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE8B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001069d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1069D 17468 bytes
SHA-256: 31da2777f5a6c2cb834816ebac200e9bbd7f3b16c8875452c52a17bd606bb5a6