Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f9842ecbcc80235…

MALICIOUS

PDF

72.3 KB Created: 2021-07-01 19:29:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 267e6b47dd827e00f45e9eda84588f60 SHA-1: 4c537ad120412d9ad36cf2842246997780a13729 SHA-256: 8f9842ecbcc80235fbe1769e2444c8871f3a5b81ba6b87deb5758ad716b94e97
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites, identified by heuristics as a link farm on disposable hosting. ClamAV and an ML classifier also flagged this PDF as malicious, specifically as a phishing trojan. The primary attack pattern involves directing users to these compromised sites, likely to host further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160830aac6c457---tesulifafapituradetogisid.pdf In PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/093e668777b4699f511e27ee43c1cda9/17445512031.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c9710aed4cc---mafejiv.pdfIn PDF document text
    • http://maekuangudomthara.com/ckfinder/userfiles/files/wiridexijupipuk.pdfIn PDF document text
    • https://akarchlight.com/wp-content/plugins/super-forms/uploads/php/files/9fdd2609e4042cd0496bb84e78b10280/xevufejebikezibobudu.pdfIn PDF document text
    • http://starlightcelebre.org/clients/4/43/43e9139217482d7666ce300faf566241/File/livoxufonegu.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073904e41016---pejidafuxukekedozopir.pdfIn PDF document text
    • http://centronegozi.com/public/zewaw.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/vitijoruvudadaxop.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/b7e9e9791a01e9f0d049628e615c2257/wuburovukoxejepoko.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/5c309u42j3kgirb42kjntcq6u4/62636789693.pdfIn PDF document text
    • http://nusamulticentralestari.com/Uploads/userfiles/files/dulepefifopebafilo.pdfIn PDF document text
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/19b6c35a0258601cd9de8f75c9a3adcc/toxakiz.pdfIn PDF document text
    • http://purpledoorchurch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfeded697f---tuseruv.pdfIn PDF document text
    • https://papiratisk.cz/soubory/66734437335.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/457eru0us06qjq8isp4eqpm4sc/xafuxa.pdfIn PDF document text
    • http://partnerplus30.ru/images/fornews/files/49004601249.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088ea2c8086e---zojegudodovotamiz.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/1b900c7c76dc301aa8dea495e9f90fd6/gujuxurexebak.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/48063056983.pdfIn PDF document text
    • https://cecprint.com/images/file/xipemitutarexadob.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1607016efe5292---junope.pdfIn PDF document text
    • http://marketypik.pl/zdjecia/fck/file/dojevuduvijuvedeleto.pdfIn PDF document text
    • https://tasteadmin.com/ckfinder/core/connector/php/custom/wysi_uploads/files/lazifuxuzinu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=extensive+subsistence+agriculture+ap+human+geographyPDF 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_off0000ba74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA74 15200 bytes
SHA-256: 81d2d1f938f495b240a0e877aebe951af7512938f2590c784b25ea4dc954c13b
font_01_sfnt_off0000e13e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE13E 11328 bytes
SHA-256: dcf2e203e1d6ba8a5c080f8790aa4e6307fdfee1c5ef1fe1450f5b5eeaf0b1a9
font_02_sfnt_off0000fb9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB9A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1