Malicious PDF — malware analysis report

Static analysis result for SHA-256 90f5ecbbb9edfdbc…

MALICIOUS

PDF

89.7 KB Created: 2021-09-03 01:01:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d21c681b175f5ea6616bd87c4d8e95ab SHA-1: cf91ec0628cc5d12e943699149b3ea01d4583f3d SHA-256: 90f5ecbbb9edfdbcb237196e8ed98d16811e93441bd4bae253c0b8ac22146072
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous links to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards an attempt to exploit users by directing them to potentially harmful URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://zrdb-drogbud.pl/Upload/file/dorufevufebiliwinevudu.pdf In PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/g107857h7c81c5156kliua40kl/sapetinubeduziliwuxedu.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160920ec85cd51---84582590485.pdfIn PDF document text
    • http://forumcutuca.com/ckfinder/userfiles/files/fonudagimuzorosumaxupi.pdfIn PDF document text
    • http://devison-matras.com/upload/file/91239461990.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16085a1b845b36---figufo.pdfIn PDF document text
    • http://minhvuongthuphap.com/upload/ck/files/97008119453.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/8n38up4jf2b8gkoce6rfu8i0il/51868000945.pdfIn PDF document text
    • http://proxima-design.cz/files/file/lobobumoled.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/e6f607335ddf52cdf1b6a7367aaf9df2/30848032755.pdfIn PDF document text
    • http://augustaelectricalwork.com/editorData/file/kutivuxomoterama.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160be75a3e23c0---doxalofutedeve.pdfIn PDF document text
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/dec7dc62edaf5c8d1ca37d7175db754e/molanafekatu.pdfIn PDF document text
    • http://ranch.pl/files/file/lisebidudozidefeku.pdfIn PDF document text
    • http://veterani-pushkino.ru/userfiles/files/guxawibit.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/3b21947f5b84c2867436ec26306631f4/lomozer.pdfIn PDF document text
    • https://medius.sk/userfiles/file/julajexo.pdfIn PDF document text
    • http://twfindia.in/userfiles/files/gigurirawaxubaserixinuvit.pdfIn PDF document text
    • http://kuzfarm.ru/images/file/tolud.pdfIn PDF document text
    • http://lahma.pl/_u/userfiles/file/nidudamimogojuvabagefo.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d3f63b8e1a5---2231149959.pdfIn PDF document text
    • https://rpdev.org/ckfinder/userfiles/files/77308044732.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/929cjrbii87f1br4bqcm94c5p0/4263076001.pdfIn PDF document text
    • http://alteredcompta.com/buddha/ckfinder/userfiles/files/jemomatakemipubegaluk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=frigidaire+top+load+washing+machine+manualPDF 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_off0000f746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF746 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010f5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F5D 11124 bytes
SHA-256: 1bcf6304e9cd216108c06cc59b991ef4bdf25b9df958d8e5dbbb8e438cb30ba7
font_02_sfnt_off000128ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128EA 18544 bytes
SHA-256: 08c67cb51af9904581d652ef8a126a279f8411babbc4428c103016ded8922a3e