Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd931df3cf37420b…

MALICIOUS

PDF

72.2 KB Created: 2021-09-25 13:50:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b995cfe3d6650bf898fbf233a27bae3f SHA-1: 1d10f9bf64256eecf332b93627b3e3c0c23a009c SHA-256: bd931df3cf37420bed159b8382b730314f23606c56c8dc93dabf4de9fa5dc61d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' indicate a pattern of using these sites to host or redirect to PDF files. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://infrive.ru/uplcv?utm_term=alex+smith+project+11+full+episode+free PDF link annotation
    • https://sahodayabbsr.com/test/fckeditor/file/sezofipike.pdfIn PDF document text
    • http://ytbozhuo.com/upload/file/122347174803.pdfIn PDF document text
    • https://latrinquette.com/upload/editor/file/dosekuniwaboz.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bfc02c23ac---ninenetedojabo.pdfIn PDF document text
    • https://careerexpo.alljobsinliberia.com/ckfinder/userfiles/files/kodupizapina.pdfIn PDF document text
    • http://themadthinker.com/temp/vinney/HTML/userfiles/file/7707542244.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/nasekofaredojuru.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16135b1075e4ff---datidadebomekefemes.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16141cacdb87ef---sejufozojujipipugakap.pdfIn PDF document text
    • http://vako.vn/app/webroot/uploads/files/61029769576.pdfIn PDF document text
    • https://ons-station.com/editor_upload/file/3475105876.pdfIn PDF document text
    • http://bamor.org/userfiles/file/40434977298.pdfIn PDF document text
    • http://yanartekstil.com/firma/files/72909817441.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/zawixokowemeka.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/76798099563.pdfIn PDF document text
    • https://cvssteelex.com/ckfinder/userfiles/files/1772385780.pdfIn PDF document text
    • https://sudhirsachdevaclasses.com/ci/userfiles/files/17433322999.pdfIn PDF document text
    • http://abbwingslynnhaven.com/uploads/files/gevogitagoparel.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/mizamemipufewemobug.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/47607366531.pdfIn PDF document text
    • http://ecilingirler.com/resimler/files/28028962050.pdfIn PDF document text
    • http://zenobiacultura.it/userfiles/file///44370743707.pdfIn PDF document text
    • http://okvin.org/userfiles/file/xasokufi.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/76986270113.pdfIn PDF document text
    • http://deaprogettazioni.it/userfiles/files/mawotija.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_off0000b3a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3A1 10984 bytes
SHA-256: 319216eaa974950c8d6f736c9e53279359286eecce761c2d58acf7f0e81d0d52
font_01_sfnt_off0000cd25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD25 17668 bytes
SHA-256: 45b2ff39c48708c85b7c78c17cbd2306f283ee939d180c438be39735992963c1
font_02_sfnt_off0000fae4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1