Malicious PDF — malware analysis report

Static analysis result for SHA-256 f09dc1389c81acdb…

MALICIOUS

PDF

77.4 KB Created: 2021-09-20 15:06:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: b499cce6470ee15c9d3fcfc043e3a9a5 SHA-1: dd8b315ca1b7fb7c97d8226a03b9f7e9ecb45397 SHA-256: f09dc1389c81acdbb56b38e7051018fb15d7ff42f781d90188158b515b4267e1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs suggest an attempt to lure users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://laureysnv.be/uploads/files/3681658625.pdf In PDF document text
    • http://elvirajogsi.hu/ckfinder/userfiles/files/24157000416.pdfIn PDF document text
    • https://photojet.net/userfiles/file/korepijapubumap.pdfIn PDF document text
    • http://thongthien.vn/upload/files/16977271354.pdfIn PDF document text
    • http://enidental.com/userfiles/file/20210909021001.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kidewagumu.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161437f10c2bb7---14272597784.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/58171489696.pdfIn PDF document text
    • https://998.geektic.com/geektic/files/dezujijoromojixewofi.pdfIn PDF document text
    • https://keralatemples.info/ckfinder/userfiles/files/42910410133.pdfIn PDF document text
    • http://tatugigo.com/ckfinder/userfiles/files/dosogopajes.pdfIn PDF document text
    • http://pascalparrot.com/uploads/assets/file/mupubojomu.pdfIn PDF document text
    • http://andreevka.topmebli.com/content/xuploadimages/file/50606987017.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/93584904056.pdfIn PDF document text
    • http://dongsimkindergarten.com/upload/files/zimalipotalamusojep.pdfIn PDF document text
    • http://studiobonvino.com/userfiles/files/jugufofimexiderubon.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/dcf8043642982bbfa63d898c788d3b35/jasor.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/c84610152c55308f998f0f1a3a3652f6/bulokusasofajujukekinero.pdfIn PDF document text
    • https://mbamantra.com/ci/userfiles/files/mujokexudemitidajodit.pdfIn PDF document text
    • http://npi-management.org/ressource/site-image/files/63205871983.pdfIn PDF document text
    • https://my-natural-style.net/upload/files/vufowedinedi.pdfIn PDF document text
    • https://luminex.pl/upload/file/zotidoleketuko.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109160734384967.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=the+analysis+and+design+of+linear+circuits+8th+editionPDF 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_off0000c941.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC941 17148 bytes
SHA-256: a7eee530ded766d3f00e0df13d5249c0ee7f2fc6b8d6fa9667560e366e7f3ee4
font_01_sfnt_off0000f5e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E9 11140 bytes
SHA-256: 613f9ba528933d13cde3070f72c20653f4152ccbd664c7f750ab9ae58e50e5e6
font_02_sfnt_off00010fb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1