Malicious PDF — malware analysis report

Static analysis result for SHA-256 c91674f74031d8cc…

MALICIOUS

PDF

79.0 KB Created: 2021-04-18 21:14:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: eb307410c58922f31af2f134a8e813eb SHA-1: d8b3981f6acd1b0329c0be9597cc8b8c53fe54d0 SHA-256: c91674f74031d8ccf8333703b8a4646541cb17eb39c71e37bf4e8ab2a1ba1ea6
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a large number of external links, many pointing to disposable domains, suggesting a link farm or phishing attempt. The presence of embedded URLs and the PDF_SEO_LINK_FARM heuristic indicate an attempt to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://vilenefex.ru/strik?utm_term=la+catedral+del+mar+seconda+stagione PDF link annotation
    • http://milansit.space/snows_of_summerxvj6t.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446931/normal_605b7b28970fc.pdfIn PDF document text
    • https://dejutuzalusabi.weebly.com/uploads/1/3/4/8/134869317/531ea10a5c7.pdfIn PDF document text
    • https://vafiradas.weebly.com/uploads/1/3/3/9/133988778/4b80ca1.pdfIn PDF document text
    • https://bemozepe.weebly.com/uploads/1/3/0/7/130739793/7551033.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461495/normal_606b0eaee620b.pdfIn PDF document text
    • http://hellovendi.com/300190345171ipgk.pdfIn PDF document text
    • https://dunexekexafu.weebly.com/uploads/1/3/4/6/134622254/9068081.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369626/normal_6001b85e7d45f.pdfIn PDF document text
    • https://dosisusibifoba.weebly.com/uploads/1/3/4/2/134236234/fexeboge_sobivabaliteba.pdfIn PDF document text
    • https://rejejowurodesom.weebly.com/uploads/1/3/1/3/131398559/lutumelodu.pdfIn PDF document text
    • https://bidijogez.weebly.com/uploads/1/3/5/9/135993355/8157830.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417645/normal_604ae71556e72.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384655/normal_60279f3cabe2e.pdfIn PDF document text
    • https://teseresoj.weebly.com/uploads/1/3/4/6/134644138/tidoziw_poxabebonin_zeseru.pdfIn PDF document text
    • https://dirovobu.weebly.com/uploads/1/3/5/3/135319654/7594067.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/ef785157-76ad-4bf6-a823-0a001ce1e9fb/sodastream_carbonator_cost.pdfIn PDF document text
    • https://d89a15f7-21b5-45f0-b9b4-bc5b7be68842.filesusr.com/ugd/18e821_8ebc858b35214481ad8dd8aaf5f7ce7f.pdf?index=trueIn PDF document text
    • https://a1f0096d-76f5-425c-b826-5ccbd312c1bc.filesusr.com/ugd/8f8c07_b54285e126104ede892c91d1e7916207.pdf?index=trueIn PDF document text
    • https://9cc02d22-446e-415d-9686-6e49aadcb3b3.filesusr.com/ugd/aa6a08_4cc03e4adbb64875b2ec061a3ad32848.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/80b665ab-cdb9-4297-8d00-d42dfce3682f/69103156825.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6081d0a1-f8da-446a-8939-99d09beb82a0/tezuzof.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d6875791-e623-49c1-9730-4dff8cc2d41f/winter_is_coming_game_of_thrones_font.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4206363b-2b8b-49a0-b06f-ffde9fb88a2d/76662608057.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_off0000f4d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D3 5200 bytes
SHA-256: 87bde7d36c7cc65c5a5d435d22cecaf25c89ee5e1ff061fc353562e98907e749
font_01_sfnt_off0001066d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1066D 11828 bytes
SHA-256: 55683dc1c002b85681ab7dbad08e61c82561e5b132a893c1c69e2fb2c8047c14