Malicious PDF — malware analysis report

Static analysis result for SHA-256 41dba481da37f768…

MALICIOUS

PDF

83.0 KB Created: 2021-09-12 12:12:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5f06534c96c02acc1575d7c7b7533666 SHA-1: 8935d2ae07ba46f707e6a5c6b55d3350bd6e02d0 SHA-256: 41dba481da37f768be8d47d1ded13642acfe8321a63e5549ef4ee87b546d7fd3
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous URLs, many pointing to disposable domains, indicating a link farm designed to obscure the final malicious destination. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery via the embedded JavaScript and external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://perfecthospital.org/ckfinder/userfiles/files/tasuritowo.pdf In PDF document text
    • http://naturestuff.nl/siteimages/file/lebasovubofarelodip.pdfIn PDF document text
    • http://svarovani-tig.cz/userfiles/file/41381680046.pdfIn PDF document text
    • http://www.tecnologycenter.com/admin/uploaded/fck/file/98350923875.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/vowubaliwatagavidukelamuz.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/tegejejajugukevoroval.pdfIn PDF document text
    • https://ijfbacknumber.com/editor_up/99488596111.pdfIn PDF document text
    • http://shriadinathbank.com/uploads/34525124679.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/webujivo.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/vijexijezukakasuzogifumix.pdfIn PDF document text
    • http://kaizousha.com/js/upload/files/15981483637.pdfIn PDF document text
    • https://innovaciones-plasticas.com/imagenes_cont/sitio/documentos/vosevakivokuxesigefer.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/gugopanaxasibudaxu.pdfIn PDF document text
    • http://nationalcoopadvisors.com/userfiles/files/64833634944.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/60476154007.pdfIn PDF document text
    • https://farmacieitaliane.com/documenti/file/perujunowoborunuvatito.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161353fc8d5a25---bakulosub.pdfIn PDF document text
    • http://aimic.com/userfiles/file/85155963056.pdfIn PDF document text
    • https://radiosmile.hu/upload/file/pawababerid.pdfIn PDF document text
    • http://aumnat2car.com/ckfinder/core/connector/php/upload/files/79478625796.pdfIn PDF document text
    • http://yesfabric.com/images/upload/File/vamuv.pdfIn PDF document text
    • http://amsasecretariat.fr/userfiles/file/limemaremojuxuver.pdfIn PDF document text
    • https://www.truckersplantparts.co.uk/ckfinder/userfiles/files/44251599524.pdfIn PDF document text
    • https://almuhja.ps/ckfinder/userfiles/files/62576842432.pdfIn PDF document text
    • http://www.radanhorse.com/resource/files/dapitisajoma.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=tszyu+vs+hogan+livePDF 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_off0000dff1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFF1 10492 bytes
SHA-256: a343bc0e14a4054d605753329c0980deac7ecb13844dad1a1e293332f59db8a8
font_01_sfnt_off0000f7d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fe3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE3 17812 bytes
SHA-256: edd50a33c83a3fb45622d022df5863b28d80432395b585b69bbaabdd9cdb637c