Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a3e45d7ea20f1e4…

MALICIOUS

PDF

71.4 KB Created: 2021-09-22 11:13:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 66ca93571958fdedea034b1eb8d021e4 SHA-1: 9258bd4c1164fb420d1d2ab425376b95765cbf5d SHA-256: 7a3e45d7ea20f1e4636b55c6d17f7a0f32527ba8d4896233ee8bab796f693a6d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to potentially malicious PDF files hosted on various domains. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm on disposable hosting, suggesting a phishing or malware distribution attempt. No scripts were extracted, but the presence of multiple external links points towards a phishing or credential harvesting attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://pre-www.bridge-college.com/uploaded/ckeditor/files/dumiludifurekalo.pdf In PDF document text
    • http://st-ark.it/userfiles/files/15523799547.pdfIn PDF document text
    • https://tuvanthietke13-5.com/webroot/img/files/56773472627.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ad565e3b18---98497626848.pdfIn PDF document text
    • https://roshnaai.com/ckfinder/userfiles/files/wesaruweduninuzonipojole.pdfIn PDF document text
    • http://innovatepc.com/userfiles/file/miziwixepazabewot.pdfIn PDF document text
    • https://gdwtechnology.com/fckeditor/file/In PDF document text
    • http://ediliziaunoaventi.com/userfiles/files/85235751751.pdfIn PDF document text
    • http://resheto.ru/users_images/fck/file/82167992253.pdfIn PDF document text
    • http://thekreativecompany.com/uploaded_files/userfiles/files/40810035723.pdfIn PDF document text
    • http://cocoon-source-harmonie.fr/public/file/36020481481.pdfIn PDF document text
    • https://komunalno-vrgorac.hr/files/4686406461.pdfIn PDF document text
    • http://newshop.jp/archive/file/vovotopuro.pdfIn PDF document text
    • http://wingprocess.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/weweluzifitenaxokap.pdfIn PDF document text
    • http://katachizu.com/img/news/files/fagazemiku.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021090401013473499.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/nabixesowusakib.pdfIn PDF document text
    • https://kltccompany.com/ckfinder/userfiles/files/penonitibidobojum.pdfIn PDF document text
    • http://automozg.by/upload/editor/files/bonamiwawaguxabu.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/wolezodisofijukenofo.pdfIn PDF document text
    • https://deltarealestate-eg.com/userfiles/file/23344382343.pdfIn PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/10423027733.pdfIn PDF document text
    • http://aucontecnologia.com/userfiles/files/rowinelegidilumed.pdfIn PDF document text
    • http://onthebroadway.com/CPD/adminpanel/upload/file/wemajamomimimibeva.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=wife+funny+quotes+in+tamilPDF 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_off0000b4e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4E1 16312 bytes
SHA-256: fcc3faec1ba795fd1c6210e2d6679c16f9a081cf1d7b767fda40fc0d36662c9b
font_01_sfnt_off0000de8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A1 10628 bytes
SHA-256: d0f36e8384ffd3338c47e072f376931a9dc505b925bfafbf577db9a424a21388