Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f483e9d069465c4…

MALICIOUS

PDF

74.1 KB Created: 2021-09-20 16:46:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7a72b5d87c621da9004ea3cb5b33e2a6 SHA-1: 54ac61fda2515e0d697b9c226cac652d15615823 SHA-256: 4f483e9d069465c4fd5769cbd1fc3bd659d84573678f4a103f3fd33a36406cf1
216 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users. The critical heuristic 'SE_SECRET_RECOVERY_LURE' indicates the document's intent to solicit sensitive recovery information, such as private keys or backup codes. While no scripts were directly extracted, the ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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://tv-kitchen.ru/files/files/92238136417.pdf In PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/16146d5d6887a4---kidudixu.pdfIn PDF document text
    • https://trade.inter-ural.ru/ckfinder/userfiles/files/10220640027.pdfIn PDF document text
    • http://ciatic.saintelserver.com/archivos_editor/file/14253694758.pdfIn PDF document text
    • http://proleague.dk/userfiles/file/93815528432.pdfIn PDF document text
    • http://indexone.ru/upload/file/53587642037.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fecbce3c92---birelazo.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/18986994153.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/danubumimibalejusoz.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/15683278502.pdfIn PDF document text
    • https://rafautama.com/uploads/file/gamuxipokitolazidoso.pdfIn PDF document text
    • http://dragonspond.com/uploads/files/nisosubotonozamu.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16146b3faaec64---zovimuzofuwexox.pdfIn PDF document text
    • http://briztravel.com/upload/files/wesarezilumomixorapewize.pdfIn PDF document text
    • http://uniquecharacters.com/upload/files/nuzexunivuzupujuruxomado.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/62013194571.pdfIn PDF document text
    • https://mtmhomeschool4art.com/mycms/uploadedimages/editorUploadedImages/file/87144705190.pdfIn PDF document text
    • http://ascensionchina.com/userfiles/file/bujem.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613f7302b915d---59373024167.pdfIn PDF document text
    • http://hyundainhapkhau.net/upload/files/digotonekogekemebajujew.pdfIn PDF document text
    • http://salt17.com/userfiles/files/26095455765.pdfIn PDF document text
    • http://insureavisitor.com/userfiles/file/81923911043.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/doporupudedemewiguvari.pdfIn PDF document text
    • https://magicdiscoradio.com/userfiles/file/22592517906.pdfIn PDF document text
    • http://ozdermusavirlik.net/userfiles/file/ruzavibopej.pdfIn PDF document text
    • http://pokrowce-ochronne.pl/Upload/file/kuxobepub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=android+best+ssh+clientPDF 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_off0000c1b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d9ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CA 16180 bytes
SHA-256: ac74e66bf8d99054f0fdcbccc907b97dbe989f8b3d785b80244fb93db312acfe
font_02_sfnt_off00010311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10311 10424 bytes
SHA-256: cc9f64b8147179bd4054f2e253fcba2f46e1c5a5a21e35ccf8771921a4b9df1f