Malicious PDF — malware analysis report

Static analysis result for SHA-256 97a77a82d8193b2d…

MALICIOUS

PDF

72.8 KB Created: 2021-03-23 13:57:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: bbe1440ed600823b25e1784450eb7f40 SHA-1: e0de457b6a3273ecef1642da84fe5eab5168c41f SHA-256: 97a77a82d8193b2dd8ae2f7ed7c6fb696e83a2d5f14cb48084729739af5115db
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, and one specific URL is highlighted as a potential lure. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or SEO spam. No scripts were extracted, but the PDF structure itself is indicative of a link farm designed to drive traffic to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://botokaw.ru/award?keyword=use+of+computer+in+communication+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4478952/normal_5fcdc2e5e9788.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368763/normal_60216d2e4ccca.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451352/normal_6021bdbdce843.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371524/normal_5ffc0d6e5910e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449014/normal_600b1debb8736.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/3b082cb7-0764-4291-b93e-e0ab254157d0/types_of_house_wiring.pdfIn PDF document text
    • https://a50dbba5-e4fd-40cc-afa9-a45495a5accf.filesusr.com/ugd/7f929b_1098e418e5574dc2bcfd8713e5f29441.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xapijifas/excel_count_sheets_function.pdfIn PDF document text
    • https://s3.amazonaws.com/belapawerezuju/bodo_video_2018_mp4.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/24d65416-bbec-449f-a3c4-1b1aaa614f28/84700952548.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ced6ed1b-315c-4e4a-a82f-40962b32e090/27896655379.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/451e11a9-686a-4b5e-b045-12ced1b15cb5/bunawowapizag.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a06b3738-8ea7-469a-a359-335ec8332ad2/24058307498.pdfIn PDF document text
    • http://voniziveput.rf.gd/28593183942.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/79071c8b-209a-4b07-a4ec-5052b8e1d315/ryobi_18v_chain_saw_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6efc9b57-6720-4d85-a44e-d608e5c3c579/kubawu.pdfIn PDF document text
    • https://s3.amazonaws.com/zasepo/4368748880.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/693a1b20-d1a9-4947-8d86-228893a811d1/runerizot.pdfIn PDF document text
    • http://fadevosozegula.epizy.com/mokivasixoxeka.pdfIn PDF document text
    • https://s3.amazonaws.com/nevovumowa/functional_training_exercises_at_home.pdfIn PDF document text
    • https://s3.amazonaws.com/somisilegex/miromimuloduguxefov.pdfIn PDF document text
    • https://28a90398-13b1-4b58-b54c-ed045a6bddf2.filesusr.com/ugd/7e9e1f_f99522d317f745b39be33529b9cf46a2.pdf?index=trueIn PDF document text
    • http://bikutuvuxaxixo.epizy.com/solving_equations_by_cross_multiplication_worksheet_answers.pdfIn PDF document text
    • https://9e77dbea-16d6-438e-9859-4a68c5388828.filesusr.com/ugd/3225da_d05e14d55d7b424c9c15826a9e0c0a71.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bed396b8-8e95-4cd6-88b9-a54fdb3fbd55/luperazuzo.pdfIn PDF document text
    • http://jigategire.epizy.com/dessert_bar_business_plan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/29a91c03-d4cf-41ac-845a-a276f2b0b422/does_zero_belly_diet_work.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_off0000dfb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB8 5260 bytes
SHA-256: a5ba62fb0288eaa9cc3d1c6f83a1c2c0c0403f5dd0e091f1ff78cd24de2065bc
font_01_sfnt_off0000f185.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF185 10372 bytes
SHA-256: c4889009a3fd1f3aabd9b2063bf8abf455a076d1e573b7ae9110816ce6000320