Malicious PDF — malware analysis report

Static analysis result for SHA-256 b670c6f6af7135ad…

MALICIOUS

PDF

112.1 KB Created: 2021-09-12 02:33:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 56b750b6c4cafabe7df2566592a3d900 SHA-1: 55740f8d1fbe81cd8f93d430ade292057a88698a SHA-256: b670c6f6af7135add40da75e151f3c38ae0bfb6bd85fe58d873ec7c707b9f9c3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous embedded URLs pointing to disposable domains, suggesting a phishing or malware distribution campaign. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a link farm designed to redirect users. Although no scripts were explicitly extracted, the PDF structure and heuristics suggest it's designed to exploit vulnerabilities or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://medvor.ru/uplcv?utm_term=shakespeare+midnight+summer+dream+pdf PDF link annotation
    • http://bebaldebaran.eu/userfiles/files/gebevijukatanukeludaju.pdfIn PDF document text
    • http://noithatlekhanh.com/Images_upload/files/53434586811.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/15842862210.pdfIn PDF document text
    • https://tsydesign.com/userfiles/jws/files/89112845418.pdfIn PDF document text
    • http://sevenseahotel.com/uploads/images/files/67511999181.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/rakowoxozofizijorajato.pdfIn PDF document text
    • http://jadever.vn/Images_upload/files/mejut.pdfIn PDF document text
    • https://nhatngudongkinh.phapluatvietnam.com/upload/ckupload/files/66256035478.pdfIn PDF document text
    • http://24cvety.ru/upload/files/186860995.pdfIn PDF document text
    • http://mrcookie.tw/upload/editor/file/102011143460.pdfIn PDF document text
    • http://veraschwemmle.de/fckdata/file/6650924006.pdfIn PDF document text
    • http://gpe-el.pro/ckfinder/userfiles/files/wasirevoragojedexe.pdfIn PDF document text
    • https://ripedzn.com/app/webroot/files/fckeditor/file/95977210857.pdfIn PDF document text
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/befotizusade.pdfIn PDF document text
    • http://coquicart.com/ckeditor/ckfinder/core/connector/php/uploads/files/5581546903.pdfIn PDF document text
    • http://amghanoi.com/images/ckeditor/files/2066261479.pdfIn PDF document text
    • http://an-ocn.ru/ckfinder/userfiles/files/tujojirixoporivumupanut.pdfIn PDF document text
    • http://wuyioutdoor.com/userfiles/file/13915807732.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f212903bf7---49422563159.pdfIn PDF document text
    • http://aokunoil.com/ckfinder/userfiles/files/ripujasarewa.pdfIn PDF document text
    • http://okzawidow.pl/img/upload/files/dabadebugunuli.pdfIn PDF document text
    • http://montagnobozzone.it/userfiles/files/54919041490.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/82726883108.pdfIn PDF document text
    • http://skmsm.com/userData/board/file/vopapupuresasu.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_off000151c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x151C3 18288 bytes
SHA-256: f8dd17b2a01ea40e399dd7b4083120201b62984ca7a30d4e6da9172e327f3c35
font_01_sfnt_off000180fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x180FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00019915.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19915 11048 bytes
SHA-256: 8b162717f484f9303941581df480d15fc0d8f8c82e77db6b924f57fb17cf5986