Malicious PDF — malware analysis report

Static analysis result for SHA-256 961d73f5e835840b…

MALICIOUS

PDF

84.2 KB Created: 2021-04-11 12:13:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: a066c38515405b611433cb3c5d5eed66 SHA-1: 18dc2b896e5feaa85c597043147569d0ffb4d1ba SHA-256: 961d73f5e835840bbd69770c1e8d8a1c297b589877c08f6667f602ad6634a344
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 0.9997

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://druttle.ru/strik?utm_term=ap+physics+student+workbook+answers PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4369518/normal_5fccd87e30159.pdfIn PDF document text
    • http://telozurilesojo.sportsontheweb.net/occupational_safety_and_health_malaysia.pdfIn PDF document text
    • http://jefuvodavi.iblogger.org/rezukuwim.pdfIn PDF document text
    • http://tizadejaso.getenjoyment.net/cuadro_medico_asisa_granada.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415292/normal_6035dabb9dfe6.pdfIn PDF document text
    • https://lijepaxo.weebly.com/uploads/1/3/5/3/135324298/44ca881fc57e28.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495402/normal_60586425d7a0a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383702/normal_5fcb4a56dbc3e.pdfIn PDF document text
    • http://pogawubujogeje.mypressonline.com/wordpress_admin_password_reset_phpmyadmin.pdfIn PDF document text
    • https://parafobosa.weebly.com/uploads/1/3/1/8/131857791/7278506.pdfIn PDF document text
    • https://xotixonivared.weebly.com/uploads/1/3/5/3/135347444/jejupixawibuna.pdfIn PDF document text
    • https://xoverepidagagit.weebly.com/uploads/1/3/4/4/134469055/zolajoralob.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4377381/normal_5ff2e252ba42e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://3745348a-78a0-42d7-8ff4-af2b45bf5faf.filesusr.com/ugd/02631b_b09e4ccd0fd14e189b3584238a3f0992.pdf?index=trueIn PDF document text
    • http://ruzupaxenerod.epizy.com/nitikerufizuxetepor.pdfIn PDF document text
    • https://a1f0096d-76f5-425c-b826-5ccbd312c1bc.filesusr.com/ugd/8f8c07_c63273db07944ca6893220f545bfd052.pdf?index=trueIn PDF document text
    • https://c4fca8c4-0f54-45c3-ae88-320069d86c16.filesusr.com/ugd/ac0d21_6d134103e9494fee8ee474c9f0e8366e.pdf?index=trueIn PDF document text
    • https://4a5bfc55-71df-4474-8f3e-9f6aca65c64b.filesusr.com/ugd/29b6ce_f3e740c30e0c478ebef8c64f34a07b02.pdf?index=trueIn PDF document text
    • http://vekemelegewimo.atwebpages.com/mobibuvonakasiwasasemutiw.pdfIn PDF document text
    • http://kuxemozoxabonag.onlinewebshop.net/ripumapaxulisutibamomu.pdfIn PDF document text
    • https://7abbf572-6989-4614-8246-9d5ba34cd238.filesusr.com/ugd/af841b_65f8329b894d4b0a957c0fb847fa6d7b.pdf?index=trueIn PDF document text
    • https://d86ad34a-7df2-4f47-937b-a12ab5abc0fa.filesusr.com/ugd/8cbfce_23ea12cfea2e4ab7add3e3295ba4824d.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_off00010583.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10583 5516 bytes
SHA-256: 82f1d1173d224efbefb3b2463f69563dea34e708c8ded485f21b8d5b86b1cfee
font_01_sfnt_off00011853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11853 12224 bytes
SHA-256: fe8ce6850411060e32f594f9202f5a689b0060b4b018cb4edc663bfb0b937552