Malicious PDF — malware analysis report

Static analysis result for SHA-256 efdc4d94ca195d9f…

MALICIOUS

PDF

84.0 KB Created: 2021-06-14 11:36:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 7f162f67097e04c25832edef7d1c654b SHA-1: 1990573f516e7cb72c552b6a4a0e49e54e7137d9 SHA-256: efdc4d94ca195d9faed7957566d2141c2228e086bb45937aa6fa77cbd70fe6bc
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm heuristics point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://garglob.ru/pbw?utm_term=zoology+practical+book+for+bsc+3rd+year PDF link annotation
    • https://nokajadum.weebly.com/uploads/1/3/4/8/134887388/6950117.pdfIn PDF document text
    • https://somejenever.weebly.com/uploads/1/3/4/3/134385140/ruvunoj_jabejalaza.pdfIn PDF document text
    • https://gimeboxevamovuv.weebly.com/uploads/1/3/4/4/134494840/7543892.pdfIn PDF document text
    • https://lakerevuko.weebly.com/uploads/1/3/4/6/134654656/mugewosowitujezaxum.pdfIn PDF document text
    • https://jatuxifukonexe.weebly.com/uploads/1/3/4/4/134469885/mibet-kamojuleger.pdfIn PDF document text
    • https://bigififipajug.weebly.com/uploads/1/3/4/7/134709095/e94d2b32ce.pdfIn PDF document text
    • https://xonuveviriniw.weebly.com/uploads/1/3/0/7/130738603/sixubotiwopedem_zawodeb_mugiruturabawaf_keradazoxof.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/3ad4e1fe-e450-42d9-8eb5-60a02247e82a/41004940895.pdfIn PDF document text
    • http://negekovav.pbworks.com/f/tombstone_unveiling_invitation_template.pdfIn PDF document text
    • http://magobok.pbworks.com/w/file/fetch/144497649/85113070738.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9f24cb38-0c17-4e59-a5a6-15ff96e05f67/rokamogezivebigebatuxeku.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2180f68e-517f-4570-a985-0c026d35beca/99081817748.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ecff0ebe-a08a-4d65-91bc-a5e1c4938354/wheres_waldo_dinosaur_puzzle_answer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6e5b9692-6ff4-4380-929f-f9f320155796/my_favourite_food_paragraph_for_class_three.pdfIn PDF document text
    • http://masigali.pbworks.com/w/file/fetch/145241169/latikapipiva.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/809b27eb-8007-46b7-8932-fabf89ac307a/biblia_reina_valera_1960_online_con_titulos.pdfIn PDF document text
    • http://padimagofo.pbworks.com/w/file/fetch/144453450/is_star_trek_fleet_command_offline.pdfIn PDF document text
    • http://xuzutoli.pbworks.com/w/file/fetch/145172574/xodefikegimadawigi.pdfIn PDF document text
    • http://mupalunava.pbworks.com/w/file/fetch/144754545/export_file_to_excel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fd99d0e0-45e7-4538-bf89-ba8b7731bb01/why_is_my_weld_not_working_on_cricut.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b26abf25-df5c-474d-a227-286391fdcc94/23791032977.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1704ed15-74fe-4bb0-84fa-f64e6ff34c59/introduction_to_calculus_and_classical_analysis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9007e3b3-0a6e-47c1-8c22-a235ade612b7/32861161081.pdfIn PDF document text
    • http://dejulagimu.pbworks.com/w/file/fetch/144533775/7_mountain_mandate_youtube.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_off00010b21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B21 5748 bytes
SHA-256: d22afbcf96cc8efcb4bc8e65df2cf7fa39b18345f980deba7cba2dc8071915a5
font_01_sfnt_off00011ecb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ECB 10472 bytes
SHA-256: eb4efc14025b0b25ac8a3c8284702eec0d5442cda8408787300d9a032a25bbaf