Malicious PDF — malware analysis report

Static analysis result for SHA-256 c81f9a2e95f5f3fb…

MALICIOUS

PDF

72.1 KB Created: 2021-03-17 19:05:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: eda0e15d3dcd2a98d5ba1cdb0c6933d4 SHA-1: b82353236089eb5bcc747b28c4482d141be2341f SHA-256: c81f9a2e95f5f3fb10db160d99c1b7f043aca27e1d4f308fc6a1eb836cab1715
186 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics as a link farm and by a machine learning classifier as malicious. It contains numerous external URLs, many hosted on disposable domains, suggesting an attempt to distribute malicious content or conduct phishing. Although no scripts were explicitly extracted, the PDF structure and link farm heuristic indicate a high likelihood of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://fokemale.ru/strik?utm_term=which+is+better+juniper+or+cisco PDF link annotation
    • http://levotavo.scienceontheweb.net/17567517099.pdfIn PDF document text
    • http://xejepurefe.scienceontheweb.net/tracce_d_amore_zhang_ailing.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478932/normal_5fdc6bc7ceb52.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487905/normal_600cfaedddfc0.pdfIn PDF document text
    • http://tonilakifak.mypressonline.com/swtor_update_6.3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376098/normal_601b9586ef26f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379474/normal_5ffea48999dcc.pdfIn PDF document text
    • http://pimifawimonidij.mywebcommunity.org/62667596189.pdfIn PDF document text
    • http://gegebafebofad.scienceontheweb.net/salesforce_crm_interview_questions_and_answers.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://miganuvag.myartsonline.com/97542562531.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8def3520-151d-4175-be3a-ca7076101595/93184213987.pdfIn PDF document text
    • http://jimomurapujivo.onlinewebshop.net/difinonuxowixugefeki.pdfIn PDF document text
    • http://lusajafimaneru.myartsonline.com/68797527027.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/75115c7b-75ca-4040-ba8d-c0b433529a5a/roland_spd_30_kits_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ef8771c7-4df0-47e9-ac58-342023b4f8f4/beteku.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc05d317-5ab1-4050-8d60-ae9bc2448555/22909142500.pdfIn PDF document text
    • https://486a928f-df87-4682-b39c-9199637d78f9.filesusr.com/ugd/982a49_e1c2caefde16467195287df7a66c1e70.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b12bb62-cf2a-427c-93eb-18579c907950/what_is_julian_date_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/51392628-6b4c-4519-9bd5-31f5b5e9a2a3/diffusion_of_innovations_rogers_4th_edition.pdfIn PDF document text
    • https://9cf93ecd-64ee-4ad6-afcc-f350577a7522.filesusr.com/ugd/c4dbd3_89c504dbbaba457691002416df15e6c4.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_off0000dfb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB9 5008 bytes
SHA-256: 81d4e8e65226009c03d055c26497ad08e8a768138399f3455c2f372e3b49b578
font_01_sfnt_off0000f0cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0CD 10152 bytes
SHA-256: 71523164c715fb48672bfdcac6f449ade3a90c111df4b4e0f5e28995f77639e6