Malicious PDF — malware analysis report

Static analysis result for SHA-256 20e1f77a4c778d0c…

MALICIOUS

PDF

81.0 KB Created: 2021-06-01 20:01:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 41ffba83170deca86e9752d26826cc17 SHA-1: 9ba2f5a71fab573664165cedbaf90d2c6927d27e SHA-256: 20e1f77a4c778d0c1957699dfadee73c065fdb7ba78ecfd5a5c915991dd4ae47
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://pelibifir.ru/123?utm_term=medscape+app+free++for+android PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4460473/normal_60356b20d6667.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4394082/normal_6016f0b60e0a8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384832/normal_60356151a184f.pdfIn PDF document text
    • https://faluwizux.weebly.com/uploads/1/3/4/3/134372305/larezozuzelev_kuluzunuxe_wuxepar_rugeputuwatili.pdfIn PDF document text
    • https://jepalojut.weebly.com/uploads/1/3/4/8/134863082/vofuratefubuzurakuvo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413846/normal_601043fc3f977.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416506/normal_6063bc8eab830.pdfIn PDF document text
    • https://vubedokixe.weebly.com/uploads/1/3/4/7/134716192/9871211.pdfIn PDF document text
    • https://vejiledulibona.weebly.com/uploads/1/3/4/3/134318828/nedibanufuzuzot_sovazi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383702/normal_604e2351a2551.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480149/normal_5fe1a6256786c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482854/normal_5fec6b8abb91a.pdfIn PDF document text
    • https://folumenudi.weebly.com/uploads/1/3/2/6/132681426/kuwofoforife-muwawa-wosukot-vuzodavojul.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419654/normal_601d265f24e0e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369329/normal_60031b94aeffc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410217/normal_602739053114e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4496204/normal_5fee6615c8244.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://nosiravuga.pbworks.com/f/wipizewawivitero.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3601a7bb-f4cf-4d73-a4e5-8d35c83951da/content_calendar_template_google_sheets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/15976b5f-1bf4-4b2a-9dd6-0ecc857dac5b/desidebutowejewanadesera.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8973da36-997a-48ca-b990-07c8d259a42a/setuvodowilusinofipu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/57a5bc83-a2fa-4d65-a345-3c7439750f11/dyson_dc17_animal_owners_manual.pdfIn PDF document text
    • http://kevuxezedila.pbworks.com/w/file/fetch/144470118/696812506.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_off0000feba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEBA 5120 bytes
SHA-256: 16f1fcf37868a813de54ec149cc04b2025710adff03a356907a1868821749040
font_01_sfnt_off00011048.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11048 11172 bytes
SHA-256: 8f1709361934da65230fd62f67e2ba97359eefec37d144ad5081ca1a3b598475