Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3404e1e88c4d941…

MALICIOUS

PDF

85.9 KB Created: 2021-09-20 21:08:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3ef129420ec8efc4e72321b9818703f0 SHA-1: 5301c22515c021408d96a3423fae8ec8b3808b17 SHA-256: d3404e1e88c4d941c9cdd5122301db2320d5f6d257e98da091c9c1911718b904
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress uploads and disposable hosting, suggesting a link farm intended to lure users to external sites. The document body is largely unreadable binary data, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://acp-luxusingatlanok.hu/ckfinder/userfiles/files/lukuwuz.pdf In PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/bolotupujed.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613ef9312eb8b---31867048797.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16141458338e55---ribunofew.pdfIn PDF document text
    • http://lotusburbank.com/uploads/files/nezipasosi.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161472de03db50---lukivexinekelasamezef.pdfIn PDF document text
    • https://www.esfa.bg/root/ckfinder/userfiles/files/15635357848.pdfIn PDF document text
    • https://thic.net/plugin/ce1/ckfinder/userfiles/files/73245992659.pdfIn PDF document text
    • http://hacoauto.vn/upload/files/posajikuvedepidiwotak.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/99992256619.pdfIn PDF document text
    • http://avvocatogiuliani.it/userfiles/files/gajujojogipopirubop.pdfIn PDF document text
    • http://intproplaw.com/admin/uploads/file/tofilizovapebaj.pdfIn PDF document text
    • https://fceresources.com/ckfinder/userfiles/files/gapavaxenedurur.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/buzuxukagox.pdfIn PDF document text
    • http://magendans.com/imagefiles/file/jinif.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/37d0eb8c4b728263faebf935a8d9a24b/11705372935.pdfIn PDF document text
    • http://ttc-investco.com/img/files/51991469831.pdfIn PDF document text
    • http://ergakiland.ru/files/files/xifoxozobalolorimogeri.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/silorabusodaki.pdfIn PDF document text
    • https://liepasmuiza.lv/userfiles/library/96371970180.pdfIn PDF document text
    • http://fitviewer.de/files/file/buxixugudobum.pdfIn PDF document text
    • https://braveathlete.net/geektic/files/39459859634.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+get+rid+of+cache+on+androidPDF 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_off0000ea35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA35 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001024c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1024C 10620 bytes
SHA-256: e943d070eccf8628bad1c8874d7317ece691ab07e6b9665860eec00bd16b6514
font_02_sfnt_off00011a50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A50 18376 bytes
SHA-256: aac14c034a3e7c2394f4de7a5e3a0f7caa3efb85e24219df5fc979322cbf9f4c