Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a50b6650180b573…

MALICIOUS

PDF

89.6 KB Created: 2021-04-05 13:46:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 6b15c58687eb355266148ee1e4671d20 SHA-1: cd53cfb053c653c291dfbc087118f34e5d4c0041 SHA-256: 7a50b6650180b573ee77e51653f526f2b92f469ac6952e56399a071b6f6513d0
186 Risk Score

Malware Insights

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

The PDF document contains a mass external link farm hosted on disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were directly extracted, the PDF structure and embedded URLs point towards a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://maypoin.ru/strik?utm_term=how+to+fix+a+dehumidifier+compressor PDF link annotation
    • http://sandiego-podcasts.com/8577941584o8io5.pdfIn PDF document text
    • http://stopnutristrike.ru/48525731391hemec.pdfIn PDF document text
    • http://kewugujijafe.iblogger.org/blank_answer_sheet_1_50.pdfIn PDF document text
    • http://myirn.icu/sinisisevigudo9mlgo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446917/normal_6012f8e1bb76e.pdfIn PDF document text
    • http://rawuzexo.iblogger.org/42543672471.pdfIn PDF document text
    • http://detubob.22web.org/field_trip_report_cover_page.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427091/normal_600c07022c7d7.pdfIn PDF document text
    • http://unlockdeals.shop/ketuf9bg6e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://zitorosenexof.epizy.com/nojav.pdfIn PDF document text
    • https://d8acad56-eb9a-42d1-a06c-a695c5b02328.filesusr.com/ugd/0ad6c7_d9da45634414439b9250066d9a804128.pdf?index=trueIn PDF document text
    • https://88bec3ce-9cdd-4818-a95b-bcf8ac49d1e7.filesusr.com/ugd/72df48_0c9ba7e6ed4e444a9b2e00658fb535c2.pdf?index=trueIn PDF document text
    • https://2a983b51-2e13-4971-8c1f-a5bca3ab4353.filesusr.com/ugd/e1a791_b447b854e03843dd8f4da0c4c01c2d43.pdf?index=trueIn PDF document text
    • https://4ac36a2f-1533-488b-b282-cf34cdace458.filesusr.com/ugd/bcfc12_8b16172b66534bd29d1ed34a0dfc70f4.pdf?index=trueIn PDF document text
    • https://441dbedc-201a-49d7-bb2a-292980023e2b.filesusr.com/ugd/473728_5b72996a9bd644129054b199cd29b53b.pdf?index=trueIn PDF document text
    • http://bidozuda.epizy.com/international_sales_law_and_arbitration.pdfIn PDF document text
    • https://83f018a0-8e49-44f0-b57e-805e464a5f06.filesusr.com/ugd/10a4aa_9969c092857c412e86ca40dfc9993543.pdf?index=trueIn PDF document text
    • https://1a413096-4115-453c-84a6-e19f3d0a1e7a.filesusr.com/ugd/4a2d03_b15f9a9e22ee46c29ab3aa8b33079f92.pdf?index=trueIn PDF document text
    • https://b2f3f1fb-4f3f-4d5d-be65-f5b10dce6288.filesusr.com/ugd/735189_f8b53a20ee374e76b4f68dd74ab27629.pdf?index=trueIn PDF document text
    • https://460eb545-5389-4aa9-9e78-d1074a8bca0c.filesusr.com/ugd/21a131_35d5e4a04a1b44cd849da6741e93768b.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_off00012064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12064 5484 bytes
SHA-256: b659fff657e42632362abf8785415d48f60b22dbe19f9a36a7c24b8e69ca82d7
font_01_sfnt_off000132f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132F8 11180 bytes
SHA-256: 88c0393e3439736317a6dfa0f7a7853ee7d4949f48a906d4e795839df93ff0bd