Malicious PDF — malware analysis report

Static analysis result for SHA-256 74f576f6d233bec6…

MALICIOUS

PDF

115.4 KB Created: 2021-06-04 00:00:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 99d53179e3e169c86598b8af13d329ff SHA-1: d67dd47174b6f49bf8737ca226730127f5b5b4e2 SHA-256: 74f576f6d233bec694ce65b6192dcbe5f9918d8088108c655d13fea0b9a84865
186 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics as a link farm and detected as malicious by ClamAV and an ML classifier. It contains numerous external links, many pointing to disposable hosting, suggesting a phishing or SEO manipulation scheme. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious intent, likely to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://vilenefex.ru/123?utm_term=chemistry+form+2+notes+on+salts
    • https://vusexojepaxeva.weebly.com/uploads/1/3/4/0/134096357/kiwenelo.pdf
    • https://cdn-cms.f-static.net/uploads/4424646/normal_6059e3cd897a7.pdf
    • https://gowoxavakuf.weebly.com/uploads/1/3/4/7/134702457/4418210.pdf
    • https://static.s123-cdn-static.com/uploads/4422373/normal_5fed723b1c47b.pdf
    • https://static.s123-cdn-static.com/uploads/4372105/normal_5fdf81b071af1.pdf
    • https://tozubovudifudi.weebly.com/uploads/1/3/5/9/135973827/74575.pdf
    • https://pezasagizagifoj.weebly.com/uploads/1/3/5/9/135968908/1269d0945c80.pdf
    • https://vegivuben.weebly.com/uploads/1/3/4/6/134660922/95d4f41ff3339.pdf
    • https://cdn-cms.f-static.net/uploads/4393026/normal_6035e78e4815e.pdf
    • https://cdn-cms.f-static.net/uploads/4458137/normal_600a71d9edc0f.pdf
    • https://xedatuvigino.weebly.com/uploads/1/3/4/5/134580066/rarifozutijutuxex.pdf
    • https://digojumowixev.weebly.com/uploads/1/3/5/9/135989627/rafivo-juneka.pdf
    • https://nunosutelakib.weebly.com/uploads/1/3/1/3/131383720/zabugaxaresavuf-najireguxolege-zadoba.pdf
    • https://mosatidopo.weebly.com/uploads/1/3/4/7/134731439/bfcf58b651.pdf
    • https://static.s123-cdn-static.com/uploads/4386095/normal_5fe2fcc4c760d.pdf
    • https://zojopurujemajom.weebly.com/uploads/1/3/7/5/137505046/dazexinun-notixavubidura.pdf
    • https://dupuzebor.weebly.com/uploads/1/3/4/6/134639309/7798077.pdf
    • https://cdn-cms.f-static.net/uploads/4462339/normal_5fea1aac502cc.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://fuxedemama.pbworks.com/w/file/fetch/144522513/kejomeduw.pdf
    • http://nuxawakaxaz.pbworks.com/w/file/fetch/144574341/how_bicycle_dynamometer_works.pdf
    • http://ziduzobif.pbworks.com/f/how_to_pair_anker_soundcore_life_note_earbuds.pdf
    • http://pajinap.pbworks.com/w/file/fetch/144497808/alcohols_and_phenols_lab_23_answers.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001702d.bin
2fab8e9a57214b7ef32d13e9b9b3136eb2ff781625ef5d4e34b513432dcebef5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1702D 5148 bytes
font_01_sfnt_off00018182.bin
45c53d6fad0efc285b9e198941b7881745ac60a7ed7f8d35caf26c7fb7ae6a19
pdf-font-stream PDF embedded font (sfnt) at offset 0x18182 11376 bytes
font_02_sfnt_off0001a8a0.bin
9876d0897ec9c8daf800546b62de215c972fdd6e45e85ac3a8ec620a70dbc6f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A8A0 16128 bytes