Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c28d8afb4331a65…

MALICIOUS

PDF

83.0 KB Created: 2021-05-27 19:05:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: 23330c43e7e446626bf5785a54f61470 SHA-1: b78ef3f58b292eb1458f9a7e3a27f48ba3997592 SHA-256: 4c28d8afb4331a65ce51519050e36f467ac29b913f55dfcb1188637785999ead
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm containing numerous external links, many pointing to disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to potentially harmful content.

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://bologen.ru/strik?utm_term=character+sheet+template+for+writing+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4370746/normal_6016c24855b48.pdfIn PDF document text
    • https://saguwaxofules.weebly.com/uploads/1/3/2/6/132681351/2312438.pdfIn PDF document text
    • https://gefawopunov.weebly.com/uploads/1/3/0/9/130969454/xezuzigetopidup.pdfIn PDF document text
    • https://gosedizomomusuw.weebly.com/uploads/1/3/4/3/134313056/jimaw_busimon_wanufapi_foxedamivodul.pdfIn PDF document text
    • https://fubomagasikeka.weebly.com/uploads/1/3/4/4/134474343/midosiwoxadupi.pdfIn PDF document text
    • https://sixamipad.weebly.com/uploads/1/3/4/7/134726782/a85a661969e0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490128/normal_6037b2c5226fa.pdfIn PDF document text
    • https://ligetivegivug.weebly.com/uploads/1/3/4/0/134041815/c2228ca90.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4487423/normal_5febd1d10f6a1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446492/normal_601d55ad70294.pdfIn PDF document text
    • https://saguwaxofules.weebly.com/uploads/1/3/2/6/132681351/6294441.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476281/normal_602aeb71f16d2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414164/normal_601ca2041d061.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402533/normal_6038d1e321c62.pdfIn PDF document text
    • https://radunepik.weebly.com/uploads/1/3/4/6/134617153/wekitozowazis.pdfIn PDF document text
    • https://gixoxiri.weebly.com/uploads/1/3/4/7/134707295/fb124c5.pdfIn PDF document text
    • https://gebifafotuzuwi.weebly.com/uploads/1/3/5/3/135324040/f0921e3301a234.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/a2ca17a9-46ba-4a1f-9ba7-bc34ece58244/metro_2033_redux_best_weapons_reddit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/980280ad-2c88-477c-93ce-46b2996313f0/craftsman_18_hp_ohv_intek_oil_capacity.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f3200dce-1e02-4a0d-89be-12a7303e6c19/repapabemega.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/07e2ee97-1854-4b40-8db2-39b0badf6393/conair_hair_clipper_replacement_blades.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4bc2c69f-92c2-4120-8ae1-6c936385cf83/weber_bbq_recipes_fish.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_off000106fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106FE 5564 bytes
SHA-256: 37d3db975bbac2fabebb398822f5b6636cc871f8db7f6a2f3cbddd45303aa6b9
font_01_sfnt_off000119ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119CE 10592 bytes
SHA-256: 8c538e9dc5ee263449b5f78425827c28b8b91a6dc85dc89f08859f209e8b23ee