Malicious PDF — malware analysis report

Static analysis result for SHA-256 50bf5825e2aa1828…

MALICIOUS

PDF

83.3 KB Created: 2021-09-12 19:11:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: fa0c889c4d6cad98fd742640978b5a1a SHA-1: ac66603c370ed5d43591dfce23c6a1f574340876 SHA-256: 50bf5825e2aa1828bee90ef1f03beaffed759ccfddb9601e9b760f34d1574186
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress upload directories. These links likely serve as a link farm to lure victims into downloading further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://appli-veolia.net/ckfinder/userfiles/files/5172282557.pdf In PDF document text
    • http://xedaptap.net/userfiles/file/96614686970.pdfIn PDF document text
    • http://imdad-egypt.com/userfiles/file/21092230141.pdfIn PDF document text
    • http://train-in-japan.com/images/blog/file/fezajijerabadixavowif.pdfIn PDF document text
    • http://kompassztuki.pl/Image/files/43546301234.pdfIn PDF document text
    • https://stomatoloska-ordinacija-rijeka.com/files/ponavodiwedujekebunivetat.pdfIn PDF document text
    • http://stsmcc.org/www/js/ckfinder/userfiles/files/64091740579.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16135841875011---mijozukumeziwozadenob.pdfIn PDF document text
    • http://akiisushi.com/uploads/files/36756875098.pdfIn PDF document text
    • http://honmamon-s.com/img_seminar/userfiles/file/turowibejules.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/wifinarubinazimex.pdfIn PDF document text
    • http://studioturina.com/userfiles/files/85559659948.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/d5807320c79273a00e239c6edd561a24/lubukafukaduzibupobogelin.pdfIn PDF document text
    • http://bursaceyizgelinlik.com/images_upload/files/68773090299.pdfIn PDF document text
    • http://toonesk.com/upload/xemevigodoji.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/suvedijewuwozilel.pdfIn PDF document text
    • http://www.sana-anong.com/ckeditor/ckfinder/userfiles2/files/pibazefugitazuzum.pdfIn PDF document text
    • https://www.bramfordgc.co.uk/ckfinder/userfiles/files/73364105584.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/161379e62a5afb---nasisovodoluvetomi.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/fawurulupolofowevivoj.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/6f27f2b8d014df57f3c255acd66e8715/27614327111.pdfIn PDF document text
    • http://tiramisu-o.com/yamituki-n/uploads/files/32753109743.pdfIn PDF document text
    • http://4yoga.by/pics/files/masulo.pdfIn PDF document text
    • https://zlatartopalovic.rs/files/vujiwopexegasufulutax.pdfIn PDF document text
    • https://afmiletisim.com/resimler/files/75393714724.pdfIn PDF document text
    • http://cobe-ing.it/userfiles/files/lododibiladuvupa.pdfIn PDF document text
    • http://letnipohar.cz/upload/file/65011092754.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=phone+as+microphone+appPDF 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_off0000df60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f772.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF772 18608 bytes
SHA-256: 945bdbed4132f446bf0cfb67d81e3d8b4dd4f2f8d3adaf34c24a7ab41d7f83a5
font_02_sfnt_off00012826.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12826 10496 bytes
SHA-256: 6946d8818c34699af78c24d3e4f9a1f5d9bece242155a682132d88a068b0b416