Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7fbfb18281846d3…

MALICIOUS

PDF

72.4 KB Created: 2021-04-02 18:39:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 41a10270388eace7bc79e989517dcdea SHA-1: 67e1ee27c23ef33037e53589e621f7962ff332d8 SHA-256: c7fbfb18281846d355b00145ef2009995e379836f862a712c2ec5787f51dd28e
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or SEO spam. The presence of embedded URLs and the structure of the PDF suggest it's part of a campaign to distribute malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://nipisod.ru/wix?keyword=module+2+physiological+factors PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4502819/normal_6013b0c3410d5.pdfIn PDF document text
    • https://luzulobopado.weebly.com/uploads/1/3/2/6/132681737/d7383.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474739/normal_604388e3ed3f5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374024/normal_6023cc7b26924.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393029/normal_605d76dbb1121.pdfIn PDF document text
    • https://nutifikidejuz.weebly.com/uploads/1/3/4/3/134347692/ridemaduvip.pdfIn PDF document text
    • https://fotofewoxa.weebly.com/uploads/1/3/4/8/134849098/rujizuwixemi_tonekiwugudaku.pdfIn PDF document text
    • http://luxuwum.mypressonline.com/anorexia_bulimia_y_vigorexia.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4394066/normal_5ffcefb7502af.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4472774/normal_5fdf67435c2db.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388813/normal_604a03d272e0d.pdfIn PDF document text
    • http://katipef.medianewsonline.com/radesejozavefoni.pdfIn PDF document text
    • https://lupagizan.weebly.com/uploads/1/3/1/6/131637074/lakoridewejaj_dalizovagopekuf.pdfIn PDF document text
    • https://mojivuza.weebly.com/uploads/1/3/0/7/130775228/bifaxugamerotu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://pekafujojef.onlinewebshop.net/lujolotaxi.pdfIn PDF document text
    • https://5902ff30-e651-486c-ac37-3e8383bfa78f.filesusr.com/ugd/f35da0_ad17962344ce4a629bd8b42f7e467116.pdf?index=trueIn PDF document text
    • https://ce2645ba-e89a-43d5-afff-5c0150757291.filesusr.com/ugd/c63dba_ef032a3b76734281a71157d7cb762149.pdf?index=trueIn PDF document text
    • https://0f7a2101-273c-4f7f-b1fd-079d1ad923c1.filesusr.com/ugd/a7ea6f_461e9b315b194d63b6e7c55f7ba5f1be.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/ruzaganog/anatomie_l_appareil_digestif.pdfIn PDF document text
    • https://s3.amazonaws.com/towakog/types_of_curriculum_development.pdfIn PDF document text
    • https://e05653fc-386e-4c8b-889d-738aee72c63e.filesusr.com/ugd/62421a_e389f05af93749d0834f74bb457c847f.pdf?index=trueIn PDF document text
    • https://8acf0fc4-2da8-4686-9788-d7840b5449fc.filesusr.com/ugd/fab691_b74db722b3184f0e8a928456bcc08e1c.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_off0000dc11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC11 5656 bytes
SHA-256: e151a54accc6bac91bcede97d4adc566b8f7f9f904b3bc6199a738b6f2a42c04
font_01_sfnt_off0000ef6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF6C 10856 bytes
SHA-256: 42e23c95aecae40d8c06272dfe1667c5bb5c97ea14d7cbdf55510477a3c0741a