Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3f99cb9838f2103…

MALICIOUS

PDF

74.0 KB Created: 2021-09-20 05:46:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6577175d863975106940cadfd014b5bb SHA-1: 28b35abe160381e67b3843a8c4fe03c577fe706f SHA-256: a3f99cb9838f210326bb6ad0b3c72e75fffbe5017543301907af4db1107193b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains a link farm with multiple URLs pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of external URIs and link farm heuristics indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://libertyrealestate.in/ckfinder/userfiles/files/mifawijikofavitokesi.pdf In PDF document text
    • https://pui-vital.ro/msg_media/file/rodigawenexarugadejazijog.pdfIn PDF document text
    • https://profession-your-dr.com/uploads/files/202109171423406535.pdfIn PDF document text
    • https://8foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/varozinezok.pdfIn PDF document text
    • http://hotel-gerard-dalsace.com/upload/document/74142651957.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/5b98h9cbmv6d27b4hq6h1icj6m/18480870256.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613454b77658f---fudut.pdfIn PDF document text
    • http://studiodebiaggi.eu/userfiles/files/denujaxavaxetopobusadex.pdfIn PDF document text
    • http://f1-rennsimulatoren.de/userfiles/file/wimirugelegigetuz.pdfIn PDF document text
    • https://12tiga.com/contents/files/nezaf.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161416d901ee6b---558732376.pdfIn PDF document text
    • http://karinameal.com/imgdish/files/fisax.pdfIn PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/toxalurimemerirutusawi.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/202195187307593.pdfIn PDF document text
    • https://stcc-sa.com/motakamel/Ups/files/97415943912.pdfIn PDF document text
    • https://irantruck.ir/data/file/76202635349.pdfIn PDF document text
    • http://odumakus.com/uploads/files/sunamudewala.pdfIn PDF document text
    • https://elesud.it/img_pagine/file/94624044372.pdfIn PDF document text
    • http://remont-elektro.eu/archiv/file/88336347508.pdfIn PDF document text
    • http://nzozkrowodrza.pl/uploads/editor/file/kafemidevaru.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ffa59e659---23453885325.pdfIn PDF document text
    • http://nordicwalkingturak.hu/_user/file/suxuxuxukadunit.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/90325957527.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=mi+box+s+vs+raspberry+pi+4PDF 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_off0000bf36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF36 16564 bytes
SHA-256: 280327aba7fd294b6e8c0163c89828200190c3390305e24ea2cb66bf32a85de6
font_01_sfnt_off0000ea05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA05 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001021c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1021C 10488 bytes
SHA-256: fd5b68589dd1bb4b2f9f7b04b41a0a3aa2abf2d3f1025a22140208dcd6071b09