Malicious PDF — malware analysis report

Static analysis result for SHA-256 640fbf40c63404c3…

MALICIOUS

PDF

72.2 KB Created: 2021-09-29 06:16:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 21194c6086abc4df5145f6ad0d78a6ec SHA-1: d56847998c3c166192c4eafed3e6af519ebadd1a SHA-256: 640fbf40c63404c31e90c4fbed1d0ec5fc4c2705f88cb0c4c1dc28c49c9a2be0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics confirms the link farm nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://pixomot.ru/uplcv?utm_term=watch+friends+season+10+123movies PDF link annotation
    • http://bobhendrix-law.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lelogi.pdfIn PDF document text
    • http://chaukitchen.com/uploads/files/tesalunamarifurupetowu.pdfIn PDF document text
    • http://happyland-nsk.net/ckfinder/userfiles/files/73058691542.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/wanekozivexogevejeke.pdfIn PDF document text
    • http://eotp.info/sites/default/files/fck/file/64222328399.pdfIn PDF document text
    • http://weddingdove.tw/uploads/files/202109061629385604.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161539381b7f88---5828592580.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/34299120911.pdfIn PDF document text
    • http://www.sospapa24.com/lib/ckfinder/imgupload/files/34423646618.pdfIn PDF document text
    • http://quanhoangtsi.com/upload/quangtri/files/vuwedokapovo.pdfIn PDF document text
    • http://nanoservice.cz/upload/file/tigetesajob.pdfIn PDF document text
    • http://diakmelo.hu/ckfinder/userfiles/files/66094918830.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c28a774cdd---sapebafufamegatux.pdfIn PDF document text
    • http://aviafond.ru/userfiles/file/84514962878.pdfIn PDF document text
    • https://812423.qqtogeljackpot2.com/contents/files/23608252385.pdfIn PDF document text
    • http://4bx.pl/public/file/lusudisubunebobuxokaveme.pdfIn PDF document text
    • http://telecycling.org/files/file/85658225409.pdfIn PDF document text
    • http://macierz-grodziec.org/files/file/jovopuxejutezege.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/738772908cf14ceb5bb032bb42f9e62c/zijisegotada.pdfIn PDF document text
    • http://wernersuarez.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/mopubosuduvituzobude.pdfIn PDF document text
    • http://straps.by/ckfinder/userfiles/files/10991719233.pdfIn PDF document text
    • https://coevent.ru/upload/files/dadafefavafu.pdfIn PDF document text
    • http://av72-reklama.ru/userfiles/file/1631973227ecd89515f19117a51c49.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_off0000b132.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB132 11220 bytes
SHA-256: fd0894eaaf46466c853b4199ff0c12c8a8e4ded009b5b1392144e2b2bd30c542
font_01_sfnt_off0000cb7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e390.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE390 18132 bytes
SHA-256: 3a4b174273f50dc13b73685b10396dd32c7a95285f732558c1f5fa6097c8c4f7