Malicious PDF — malware analysis report

Static analysis result for SHA-256 fce4d81329e4a531…

MALICIOUS

PDF

81.2 KB Created: 2021-09-03 00:09:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1ef3fdb8140f85773e1087802b5e5fd1 SHA-1: f2c7f39ab1f90ce744ea211b3da4d178973c6be1 SHA-256: fce4d81329e4a531d1b8b768bed71ac1181f61d141d75a9027133f20508b594b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate an attempt to obscure the final malicious destination, likely for malware distribution or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://gachbinhduong.com/upload/file/dizuwobavuratoje.pdf In PDF document text
    • http://zuestag.ch/userfiles/files/17029735318.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/jewesulibudaxezil.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160a4164ecf2f3---59767154241.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16096b16686624---xikalikofe.pdfIn PDF document text
    • http://fairway.cc/images/blog//file/166967751.pdfIn PDF document text
    • https://cristalparkhotel.com/ckfinder/userfiles/files/35582864730.pdfIn PDF document text
    • http://gat-asset.com/CKEdit/upload/files/nafuja.pdfIn PDF document text
    • http://anandtouristcorporation.com/uploads/zivamagokojotuda.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/p6elv2lqud1lvsr8to40jfhqc3/57298616461.pdfIn PDF document text
    • https://wecareu.net/ckfinder/userfiles/files/46167189511.pdfIn PDF document text
    • http://alexhoffordphotography.com/temp/files/file/83278880941.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2ec43bbf4---logejemagubifa.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/fipefixedirobip.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/xulaniwukakebiv.pdfIn PDF document text
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/loxajerenapipovawonufug.pdfIn PDF document text
    • http://mousike.it/img_ins/files/wilozuzivopi.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/33rqn5aq9872rbfkq9jbh5bom2/goloxevinobeluwewa.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160791cf640b02---lirugibepurezu.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b19e75be51f---59923885282.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/409abfde1f576c234d743a06225a1fce/sokegamewarakok.pdfIn PDF document text
    • https://maria-galland.ru/files/file/30480609749.pdfIn PDF document text
    • http://moestuinwebshop.nl/userfiles/file/39252188704.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607c328fcc013---paxekosufajuvaj.pdfIn PDF document text
    • https://tappowine.com/file/21519183049.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/rch9e0v0ap9892qpbk1ednr365/66684647753.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=technical+sales+engineer+job+description+pdfPDF 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_off0000d9da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9DA 11132 bytes
SHA-256: abfe4f9dd29e4e0936390f5fa229abb217e142d0dfc6c97670bdbd425b753f77
font_01_sfnt_off0000f352.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF352 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B64 16912 bytes
SHA-256: b0cdd27e2056207e1b3c767c206b2c5293b595fd4ac1024cf8b71d7d32ed19da