Malicious PDF — malware analysis report

Static analysis result for SHA-256 4997ddfd8cfd7251…

MALICIOUS

PDF

81.2 KB Created: 2021-06-10 19:00:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 5e3e8f81e057c71034da739378231509 SHA-1: 316fcb65a5dcd6153366bc2a79471f3b6ec81fa9 SHA-256: 4997ddfd8cfd72512878d2f6ce494d027e78efd2d23dabb5af6ee6b9fb9836ed
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to other PDFs hosted on disposable or user-generated content platforms, indicative of a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for SEO manipulation or to distribute further malicious content. The presence of a download button lure further supports a malicious workflow.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://leonvi.ru/123?utm_term=jewellery+business+card+templates+psd PDF link annotation
    • https://menosakisidibus.weebly.com/uploads/1/3/5/3/135391165/1310805.pdfIn PDF document text
    • https://kuxevirajopar.weebly.com/uploads/1/3/5/9/135990570/761a6706.pdfIn PDF document text
    • https://tiriwubesunadew.weebly.com/uploads/1/3/0/7/130739346/bimukawonomu.pdfIn PDF document text
    • https://luzafoku.weebly.com/uploads/1/3/0/8/130814295/basavamatuna.pdfIn PDF document text
    • https://kasikijafeke.weebly.com/uploads/1/3/1/4/131406722/temejo_bemox_gesavulotajomof.pdfIn PDF document text
    • https://molipose.weebly.com/uploads/1/3/4/6/134644393/niwagifomasug_bavivutaf_demezawet.pdfIn PDF document text
    • https://kesetemokeze.weebly.com/uploads/1/3/2/6/132682820/2502289.pdfIn PDF document text
    • https://wafiludelo.weebly.com/uploads/1/3/1/4/131437380/ebf992dd8ef2.pdfIn PDF document text
    • https://fudopelotavag.weebly.com/uploads/1/3/5/3/135325828/45c3a.pdfIn PDF document text
    • https://tesebajaja.weebly.com/uploads/1/3/4/4/134402558/rijidukerew-jodurefemag-fazaka.pdfIn PDF document text
    • https://pufokebisuniga.weebly.com/uploads/1/3/5/3/135324869/fenawij.pdfIn PDF document text
    • https://voxuvuru.weebly.com/uploads/1/3/5/3/135390020/gudunomulu.pdfIn PDF document text
    • https://dubezotamepaloj.weebly.com/uploads/1/3/5/2/135297843/3c7be852076e.pdfIn PDF document text
    • https://guvikaki.weebly.com/uploads/1/3/4/5/134519546/sexolapepipak.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
    • https://uploads.strikinglycdn.com/files/30830758-538e-47d0-9bc7-1c5d45808c45/farigowa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e27a82bf-d580-46b5-ba46-e56c675e5345/4316781722.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f601a5aa-9c8a-4587-b572-52bec613fe04/factoring_polynomials_worksheet_with_answers_doc.pdfIn PDF document text
    • http://lovixov.pbworks.com/w/file/fetch/144826155/53592749993.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55219ee4-a56e-4998-9362-1a269511d5cf/skyrim_keeps_crashing_xbox_one_x.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2e9b22e2-1082-47ba-b496-208a0b3ec650/offroad_outlaws_mod_apk_2019.pdfIn PDF document text
    • http://dumunivuniv.pbworks.com/w/file/fetch/144676404/how_to.play_snakes_and_ladders.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e7d8b5c-3552-48f0-94cc-79de28c04556/kovafivutofafuv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/786afe3d-afb2-4e62-a5ad-b8c26337647b/what_is_knowledge_based_management_system.pdfIn 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_off0000f3d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D0 5312 bytes
SHA-256: 13538c6965ec43762444ba7a99e0b9d62dec66125016f8304f0e194c6ffbe882
font_01_sfnt_off000105d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D0 10340 bytes
SHA-256: 863baba8c366715612cf63771424fb3d7c85d8ec18c2166b0213b89ae5d39dbb
font_02_sfnt_off00012922.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12922 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378