Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc5791d80303c98d…

MALICIOUS

PDF

74.5 KB Created: 2021-06-09 03:42:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 667b4532b64e014d8fdc412606e17a83 SHA-1: db89c3a711b4818815f604436d58455c975e6d71 SHA-256: dc5791d80303c98dd87e3c1f49bf6c2f77b1b87bfa4d13e5f8a4a7d47e6aea3b
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics indicate it functions as a link farm, containing numerous external URIs, with one pointing to 'https://coretry.ru/pbw?utm_term=dahornet+serial+number'. The document body is heavily obfuscated and unreadable, suggesting attempts to hide its true purpose. No scripts were extracted, but the overall structure points to a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://coretry.ru/pbw?utm_term=dahornet+serial+number PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4444113/normal_6028801eb2b3b.pdfIn PDF document text
    • https://pawikewam.weebly.com/uploads/1/3/4/4/134445239/favus.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412778/normal_601345e09edd4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373782/normal_605d6891ea2a6.pdfIn PDF document text
    • https://gexawagezawa.weebly.com/uploads/1/3/2/6/132682787/potarid-roligazegivo-wanemaforu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501054/normal_60661e5b42f4d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/ae7ecd9a-a362-4f4f-b4c8-90af318984ad/lemateregodemejejat.pdfIn PDF document text
    • http://tovemubu.pbworks.com/f/36377699445.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b476bad8-4ec7-4fbb-9e63-604f91efa6bc/how_to_use_a_rainsoft_water_softener.pdfIn PDF document text
    • http://xalomuzavege.pbworks.com/w/file/fetch/144431943/actividades_de_enfermeria_en_cuidados_inmediatos_del_recien_nacido.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/71550182-cf88-4651-8087-e7bbdf6aaeb4/what_is_symbolic_logic_in_mathematics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bdc2f53a-0c69-45d9-9064-77d60db79eb1/72796433100.pdfIn PDF document text
    • http://lijunew.pbworks.com/w/file/fetch/144786513/chhota_bheem_aur_krishna_full_movie_2008.pdfIn PDF document text
    • http://sirazumebow.pbworks.com/w/file/fetch/144906063/tikunuxorepupugewigeza.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/88b2223b-1e45-44ed-8866-ac96993f47e0/life_fitness_x1_elliptical_replacement_parts.pdfIn PDF document text
    • http://xugilip.pbworks.com/f/rejosegebaluzabezesed.pdfIn PDF document text
    • http://baxikufop.pbworks.com/w/file/fetch/144886194/sewir.pdfIn PDF document text
    • http://ziriwuru.pbworks.com/f/legulekofuz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c318657-8a10-4a78-84dd-0944f28825b0/borodirosifibufegi.pdfIn PDF document text
    • http://beratirupo.pbworks.com/w/file/fetch/144875001/47647066796.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5FD 5064 bytes
SHA-256: d7bc484ff914e2b3b9504c9850378de2a184ba7453a3bf362bb6ee238653db54
font_01_sfnt_off0000f70c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF70C 10952 bytes
SHA-256: 4991dca75f806d2a78bf01fce32396711facef591bf4b2efbc7790b52b62841c