Malicious PDF — malware analysis report

Static analysis result for SHA-256 55ed6fe16e32f888…

MALICIOUS

PDF

84.5 KB Created: 2021-08-06 09:09:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0382b93c48e46132ef41cea0df299d52 SHA-1: 12c790b97b39bdb47217908b059fd8b0fc26faba SHA-256: 55ed6fe16e32f8885a9b1cd8a64b1536d568d37f6cdbc855df518225d00bdfd9
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. Multiple URLs point to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to phishing or malware sites. The presence of embedded URLs and the overall structure strongly suggest a malicious intent to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://zerosquareonline.com/file/99536933380.pdf In PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0b26dc886a---34413856138.pdfIn PDF document text
    • https://mavibusiness.it/file/57833998674.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4eb0d91c2---78026585466.pdfIn PDF document text
    • http://perseverance.cyou/updatefiles/file/19097963734.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c448e4a51---60360584178.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606dfd8413e7a---xodotosigumalibaseg.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084de15b2f6a---fulubuvogoz.pdfIn PDF document text
    • http://xn--72c7caerxx0d3a9eve.com/UserFiles/File/5977654914.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/36d3573a6e1a8699ebd68e9fdd9e454d/62045015024.pdfIn PDF document text
    • http://geo-equipe.it/userfiles/files/77328385678.pdfIn PDF document text
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/sdd1hd35du6kvtu78oahtulp75/85010376307.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/ac1356d7f4e6aecb0feaae6107fb28b4/7484191990.pdfIn PDF document text
    • http://drkoopman.nl/cmsimages/file/sikurifole.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/kupemasujolavapewaki.pdfIn PDF document text
    • https://bibliothequedesarts.ch/ckfinder/userfiles/files/taxolizerunisadevukukokur.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/efde9731f1cbc3dd22e81a6370980446/revijixukob.pdfIn PDF document text
    • https://renault-service.com/userfiles/lomatiwuvidira.pdfIn PDF document text
    • http://ues-rb.ru/themes/ues-rb.ru/files/vedot.pdfIn PDF document text
    • http://design-klasse.de/ckfinder/userfiles/files/gopirafar.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160d01cfe98ae8---79678385405.pdfIn PDF document text
    • http://isleford.com/filespath/files/20210804161435.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a87339cf85b---61943472121.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/168aa8b07ddd6ff22c888898a66ed781/wimego.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=dibujos+de+moises+y+los+10+mandamientos+para+colorearPDF 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_off0000e24d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE24D 11336 bytes
SHA-256: 2cc66c6bd5bd420fe20963be0cfdfe95e8de44e532df58d63bf42e91a551865e
font_01_sfnt_off0000fcbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCBE 17936 bytes
SHA-256: 971eb4bc09b988ac84d1a32c2d6f043d68c0e53551cc2966f4f83bb8961e1d88
font_02_sfnt_off000129ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1