Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d45942f399bd719…

MALICIOUS

PDF

68.5 KB Created: 2021-09-08 21:48:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6acb928dc967f9f77be14d26cf14c03f SHA-1: 25b7e9eb480eb10739999923f84bb16c3c9060aa SHA-256: 3d45942f399bd7199df00f2ffbf79a45206f064070c8ea591116b2f67f842633
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were directly extracted, the PDF structure and URL patterns are consistent with spearphishing attachments used to lure victims to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://renhedc.com/uploads/files/202109061421312542.pdf In PDF document text
    • https://santechnikosdarbai.lt/images/files/sajodavilok.pdfIn PDF document text
    • http://aquatherm-graz.at/files/wozazuko.pdfIn PDF document text
    • https://adetexfoamgroup.centralcms.cloud/galeria/files/14420987671.pdfIn PDF document text
    • http://rileyillustration.com/images/agency/files/98596961304.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/12274606537.pdfIn PDF document text
    • http://lideparts.com/userfiles/file/1630742585.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/92609940912.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/2cff1982b95b51740129b0752f75ee8d/polalogazelog.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/bakilijusu.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/bufuwotijopawanuwupe.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134ec473f7e0---ditimevudijinejomunif.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/mukudaromorose.pdfIn PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/lavusetifafoperopujuludi.pdfIn PDF document text
    • http://tuvantindat.com/uploads/2021-09-07/images/files/nilabagadavew.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/30254784563.pdfIn PDF document text
    • http://luatsugiadinhviet.com/upload/ck/files/2455228929.pdfIn PDF document text
    • https://mp2020.csysadmin.com/ckfinder/userfiles/files/37156633586.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613016bbd2606---73281659923.pdfIn PDF document text
    • http://linker-apps.com/files/koxalawubemofukefoge.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/24957828328.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/jezowexigosufu.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135032e3efb9---33038470087.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/lumixorugovixunefegig.pdfIn PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/fopexanupamalibufafepom.pdfIn PDF document text
    • http://xn--or3bi2da319p.com/upload/fckeditor/file/mozotosukesazugoku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=neotv+app+downloadPDF 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_off0000b0fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0FC 14584 bytes
SHA-256: 3bfccbdbc7cdc0d82298f8676066f472628697cf0e0bdec789dd754d65349fa5
font_01_sfnt_off0000d576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD576 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ed8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED8D 10152 bytes
SHA-256: b91c9558f28cc0e299e76e33503685019c395b0b0fba4d7e9da88f747c7e6baa