Malicious PDF — malware analysis report

Static analysis result for SHA-256 e744b84d3cb8280a…

MALICIOUS

PDF

77.8 KB Created: 2021-09-17 23:50:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c828b27f0751d69bbc7a26c587266afb SHA-1: 9b5e467b0b1d17114ca5113d89589d486820183f SHA-256: e744b84d3cb8280afe7bd05cc9190920784d95e7667d8e39f5a60d30a665847a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress upload storage and other disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://cremyco.com/app/webroot/docs/file/20805805309.pdf In PDF document text
    • http://savytrading.com/userfiles/file/48549458073.pdfIn PDF document text
    • http://joy05.com/_UploadFile/Images/file/datijapodixor.pdfIn PDF document text
    • http://thaiboxes.com/piceditor/file/36005463270.pdfIn PDF document text
    • http://synthecinter.com/userfiles/files/mopagubasofadu.pdfIn PDF document text
    • http://montesantangelo.it/files/files/69422014999.pdfIn PDF document text
    • http://ccsilver.kr/files/fckeditor/file/42808344061324138a24c6.pdfIn PDF document text
    • http://wic-net.com/userfiles/file/82484792622.pdfIn PDF document text
    • https://md-bud.pl/szklo/photos/file/89743866531.pdfIn PDF document text
    • http://akademia-jedenastka.pl/zdjecia/fck/file/jirin.pdfIn PDF document text
    • http://islenapuntos.com/campannas/file/zotekapisodeg.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7932af4f9---zizurat.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1613d03d19fbfd---jozaxexomarisumukasixamu.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/43392676261.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/7077f4bc967df8dd07c75ec7aac71e24/59666613838.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/vipotula.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/82664361739.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/23890347344.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614064b82c318---bumalekizedupu.pdfIn PDF document text
    • http://goldstecq.com/userfiles/file/jorasopavinijalezeg.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/nawazafalegaramofive.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/maxufan.pdfIn PDF document text
    • https://perfecthospital.org/ckfinder/userfiles/files/42341028806.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=heptane+combustion+reactionPDF 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_off0000c592.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC592 10720 bytes
SHA-256: f528dc487e0feb85ab58fca7420b35810c4d3e2743fabe2621add59550adcbdd
font_01_sfnt_off0000ddea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDEA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5FC 19744 bytes
SHA-256: 9ba6df81b9a2a9d8154aaf756b4f2ba3a41ba5cf8cfb6bf0846beb8971f244e8