Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8b3df87ed06d75a…

MALICIOUS

PDF

77.2 KB Created: 2021-06-11 02:54:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: f6323e978ba1315d9e58c55c3a313b96 SHA-1: 74fe6f4bfe819e50a45741538c8e51fce76e19d7 SHA-256: f8b3df87ed06d75a4c83dae5c46b91b8772d0483f565582cf35ad7cb4f85b7f9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document is classified as malicious by ML and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The document body, though heavily obfuscated, appears to be a lure related to 'Lord of the Flies' worksheets, likely to trick users into clicking the embedded malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://archism.ru/uplcv?utm_term=lord+of+the+flies+symbolism+worksheet+pdf PDF link annotation
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bf9e0f0b5ec---topeparevovuwad.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/dizikekatolomi.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bfa4e8575e---nenifunopilowezu.pdfIn PDF document text
    • http://kovacsoltvaskerites.hu/images/file/juwimipafip.pdfIn PDF document text
    • http://stuarteisbrucklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/80182729343.pdfIn PDF document text
    • https://stegopackaging.com/wp-content/plugins/super-forms/uploads/php/files/scapb9hqj25ogdv2pco0874roi/9588709382.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/bivsl2p5s46p7q977ookughtd7/22350107001.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/rawawevimuzajipizenogazo.pdfIn PDF document text
    • http://tingyi-bnb.com/CKEdit/upload/files/kuxila.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/43108516317.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/16093ae3d65b50---13326495884.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160773d3ac01f4---87844472440.pdfIn PDF document text
    • http://d4storonto.com/clients/e/ed/ed023a0734c265ca673a92d1d81de675/File/pegixegojavikuj.pdfIn PDF document text
    • http://mesterek.net/tmp/tunari.pdfIn PDF document text
    • http://tradeweb.es/userfiles/file/35066646342.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/52c52cd3f2cbf7e6cda50123d405904e/5956641319.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e3ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3CE 5092 bytes
SHA-256: e6161cfe81cd4e0b57e2f2ea20406df0a4fe78c3f67f3d657bd56389baec2958
font_01_sfnt_off0000f535.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF535 10672 bytes
SHA-256: bb86132f424f6a25a890e2e810968169695f0e9e3bd74a8c2011e038b213856c
font_02_sfnt_off00011992.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11992 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3