Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf087bb686f98bd5…

MALICIOUS

PDF

72.3 KB Created: 2021-06-11 10:33:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: b04943b91c6312a4120cdbe8e40a09c7 SHA-1: 723a1be62aa25b68f317e38bf3950667a4722aa1 SHA-256: cf087bb686f98bd56db1ada4b50129469bd4bd72f50070c6e6ce8e2f6616e345
186 Risk Score

Malware Insights

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

This PDF document functions as a link farm, directing users to various external URLs, one of which is a KMS activator for Windows 10. The presence of numerous links on disposable hosting and the ML classifier's high confidence score indicate a malicious intent to redirect users to potentially harmful content. No scripts were extracted, but the document's structure and embedded URLs strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://laborke.ru/pbw?utm_term=kms+activator+windows+10+home+64+bit PDF link annotation
    • https://wovuposekase.weebly.com/uploads/1/3/4/6/134613379/5497959.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386837/normal_5fd74b1fed4a2.pdfIn PDF document text
    • https://kitupiver.weebly.com/uploads/1/3/4/4/134446404/914485a86dfd.pdfIn PDF document text
    • https://juzajepilokak.weebly.com/uploads/1/3/4/6/134682244/zukide.pdfIn PDF document text
    • https://sinegozedajosor.weebly.com/uploads/1/3/1/8/131871849/4193131.pdfIn PDF document text
    • https://diwosilanula.weebly.com/uploads/1/3/4/7/134765308/tedata-zuzojoxigaka-binoxerisojun.pdfIn PDF document text
    • https://warenumew.weebly.com/uploads/1/3/4/8/134871813/2942658.pdfIn PDF document text
    • https://gizizajavime.weebly.com/uploads/1/3/2/6/132695742/6154079.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377704/normal_605bdbcb3a62c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465267/normal_5fdf39fc637e1.pdfIn PDF document text
    • https://piwaxiru.weebly.com/uploads/1/3/4/8/134882920/mejagowi-luzasajofivaf-lovabumuxazakoj.pdfIn PDF document text
    • https://dajemegexiri.weebly.com/uploads/1/3/4/4/134492390/fozib.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4377928/normal_5ff6211e3562a.pdfIn PDF document text
    • https://zigikarorusoto.weebly.com/uploads/1/3/5/3/135351373/kajepopusifo.pdfIn PDF document text
    • https://xevexotu.weebly.com/uploads/1/3/5/3/135309825/pezenezuvutitiwebir.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445889/normal_60279ed8a76ca.pdfIn PDF document text
    • https://wogilaxafa.weebly.com/uploads/1/3/4/4/134479860/binepoxox-katazamozij-botukoxi-gerugusime.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/7bc7f302-1979-4cbc-9568-02c70fcd48b6/combat_shooting_courses_near_me.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b45f482-58e2-4082-88ab-6c7ba9f10f63/14051262220.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ec2123f8-2cca-4efc-bd7f-2cf28168abc5/59194409836.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e5a272b7-d4bd-47cb-a72a-e6144a780e6d/how_to_explain_emotional_labor_to_husband.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/519154c7-6493-4f35-9247-8a4acb06289f/how_to_write_a_concert_report.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_off0000dc15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC15 5844 bytes
SHA-256: f40cb5d4468351ecc4e49382536ff68dfdebe8a54cc362a2134bfe79a1ad062f
font_01_sfnt_off0000efe8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE8 10472 bytes
SHA-256: 0b6b8bf00c2360b38ccbf021a054b09555063b5b5aa67b978e661640e3bd8b95