Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffb8422ddb695d42…

MALICIOUS

PDF

36.7 KB Created: 2020-05-20 05:41:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-08-25
MD5: 03231a0f84d75ebc6a1f330acfeff707 SHA-1: 94891422f9274336eb128e276b3d5a28699355b0 SHA-256: ffb8422ddb695d424e72ec61b4594aca902fbe034e4c0acd6d57106cbe053dd0
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The document presents itself as a free plumbing course, a common lure for phishing or malware delivery. It contains a large number of external links, many pointing to PDF files hosted on various domains, indicating a link farm or redirection mechanism. The ML classifier strongly flagged this PDF as malicious, and the PDF_SEO_LINK_FARM heuristic confirms the presence of numerous external links designed to manipulate search engine results or distribute content. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 4

  • 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.
  • 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 http://ejze.studio/uploads/1/3/0/7/130775950/130775950.html#curso+de+plomeria+gratis+descargar PDF link annotation
    • http://startupspectacular.com/uploads/1/3/1/3/131384708/kasimepajo.pdfIn PDF document text
    • http://333enterprises.com/uploads/1/3/0/8/130873735/1097533.pdfIn PDF document text
    • http://readysettravet76.com/uploads/1/3/0/6/130639643/wukuje.pdfIn PDF document text
    • http://kchungphotography.com/uploads/1/3/0/5/130551066/denanegoxi.pdfIn PDF document text
    • http://unpolishedhealth.com/uploads/1/3/0/7/130739063/tevugufe.pdfIn PDF document text
    • http://curbapparel.com/uploads/1/3/0/5/130550778/finafojejuzawar-xavuz-tesagejepofewu.pdfIn PDF document text
    • http://partridgepropertymaintenance.com/uploads/1/3/0/6/130604951/ziwonobudu.pdfIn PDF document text
    • http://ritualcoffeebar.ca/uploads/1/3/0/6/130639757/9628644.pdfIn PDF document text
    • http://leylamoya.com/uploads/1/3/0/6/130620792/tomufozanirisex-lejimefal.pdfIn PDF document text
    • http://altruisticresults.com/uploads/1/3/0/3/130313192/sodumaki.pdfIn PDF document text
    • http://elgueras.com/uploads/1/3/1/1/131164366/77c2a3.pdfIn PDF document text
    • http://paulasboutique.org/uploads/1/3/0/3/130379409/juxux_felolum.pdfIn PDF document text
    • http://italoamerica.com/uploads/1/3/0/6/130639488/kuvebukemom-nirofivabeb.pdfIn PDF document text
    • http://marcoscustomcabinetry.com/uploads/1/3/0/2/130288448/jijepuxuvufejamu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005f27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5F27 12220 bytes
SHA-256: 1d200856df98f7b4334b133aeec30ea9ee0113875650998d2fa365b5c8d2085c