Malicious PDF — malware analysis report

Static analysis result for SHA-256 5661bbdab803450c…

MALICIOUS

PDF

68.4 KB Created: 2021-03-25 07:28:14 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 4ef31fb00816dcaf0f96db07ca196331 SHA-1: 3c2607e142868fce64134a824cddf45e6ab25fa7 SHA-256: 5661bbdab803450c78ff3f3c99b6e41298f0c7d12fb5a7c3aa2bfbf93720e72a
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics, suggesting a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing malware. While no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards a malicious document designed to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • 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://kuzutuzo.ru/award?keyword=maths+practice+book+for+class+5+pdf PDF link annotation
    • http://baboguzaxeleju.mypressonline.com/65933464595.pdfIn PDF document text
    • http://povisowalikim.scienceontheweb.net/change_file_to_word_free_download.pdfIn PDF document text
    • http://majovevalaji.sportsontheweb.net/xosojurijozez.pdfIn PDF document text
    • http://wedasuf.getenjoyment.net/all_falls_down_piano_sheet.pdfIn PDF document text
    • https://zadevadetolilug.weebly.com/uploads/1/3/5/3/135321342/xefujefasa.pdfIn PDF document text
    • https://famuvotatag.weebly.com/uploads/1/3/0/8/130813835/golaluzumutevag.pdfIn PDF document text
    • https://zuxosudeti.weebly.com/uploads/1/3/4/3/134359900/tudefavixixatezizisi.pdfIn PDF document text
    • http://tevaruv.sportsontheweb.net/pilodupaniroposupogal.pdfIn PDF document text
    • http://lilubaxubaxulu.sportsontheweb.net/95062129589.pdfIn PDF document text
    • http://fupefabesosada.mygamesonline.org/bending_emt_conduit.pdfIn PDF document text
    • https://vugadeji.weebly.com/uploads/1/3/1/4/131406436/3d38b.pdfIn PDF document text
    • http://pawezujexas.mywebcommunity.org/how_much_to_rebuild_a_302.pdfIn PDF document text
    • http://supariwepexafat.mywebcommunity.org/what_is_feminism_in_literary_theory.pdfIn PDF document text
    • http://wivupivipewezap.mygamesonline.org/le_verbe_aller_au_prsent_exercices.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://f59c0a4d-c104-43ac-8966-a5978cdf1b8c.filesusr.com/ugd/0c1ebd_3354ecea60024d0688e4b8c6509915e7.pdf?index=trueIn PDF document text
    • https://203e7bc3-08d7-4ecc-a8df-f797e0d4a079.filesusr.com/ugd/d4579c_d921ee01da2e4aa2a2ef224ca2c254d6.pdf?index=trueIn PDF document text
    • https://5663e088-3595-439c-971a-5873693bee35.filesusr.com/ugd/e98895_b255246fa2ed4cec9bcf7837e1e55fc9.pdf?index=trueIn PDF document text
    • http://lumosaneja.onlinewebshop.net/washington_state_phase_2_construction_requirements.pdfIn PDF document text
    • https://8dcf3d85-40eb-4350-b789-ae6ac2c46e24.filesusr.com/ugd/21d17a_ded6b9d564b04c949f2a5c28bc5a0e73.pdf?index=trueIn PDF document text
    • https://78151a86-a557-4e49-81aa-a2539eea45c7.filesusr.com/ugd/204f4f_d9355a9aa7c14a7f817a8b087a136b42.pdf?index=trueIn PDF document text
    • https://f7cac2f2-528f-490f-9bef-cb2448a877de.filesusr.com/ugd/529ba0_0455dd93284f46e38d1464895e9b9fff.pdf?index=trueIn PDF document text
    • https://19e6fc83-c281-4d06-93fd-e8b16a02b90a.filesusr.com/ugd/ce5d00_a6712d48988346fe99ba4583eb54b3ae.pdf?index=trueIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cd32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD32 5576 bytes
SHA-256: 17569a479128d21c05436f344fc1da45f8c4ee92eb7d4f84b6740a5f9116e961
font_01_sfnt_off0000e02c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE02C 10776 bytes
SHA-256: e73a28ea7f7b0899ebcfd7cda0269ffe8411b1aeaa3299b90a28047738535dd8