Malicious PDF — malware analysis report

Static analysis result for SHA-256 f616d75968972d83…

MALICIOUS

PDF

76.6 KB Created: 2021-06-03 11:30:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: b8ad4a48f237aac93db5e9e41c871eb6 SHA-1: 04c8b1c0a0f5540baf0736517922d2b3ec24b47e SHA-256: f616d75968972d83088bd0f8da3d74decac192cb570af51bee5c099932556b42
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains a large number of external links, many pointing to disposable domains, suggesting a link farm or SEO spam operation. The document body, though heavily obfuscated, appears to be related to educational worksheets, which is likely a lure to disguise the malicious intent of redirecting users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://leonvi.ru/123?utm_term=non+flowering+plants+ks2+worksheet PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4372702/normal_6056913092076.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468571/normal_60521ee63d87c.pdfIn PDF document text
    • https://vejexuwelukilik.weebly.com/uploads/1/3/5/3/135340180/3008827.pdfIn PDF document text
    • https://tiselewo.weebly.com/uploads/1/3/1/6/131606631/migurasodofamokaner.pdfIn PDF document text
    • https://xipunozelizu.weebly.com/uploads/1/3/1/3/131382486/d5871e52af5.pdfIn PDF document text
    • https://zasoliwex.weebly.com/uploads/1/3/5/3/135318241/5103874859c8c.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/364093d4-e9e7-4f0d-8ab6-c79487047954/gisanoguzilusinituw.pdfIn PDF document text
    • http://jebusolole.pbworks.com/f/wumozib.pdfIn PDF document text
    • http://dijakezepo.pbworks.com/w/file/fetch/144437298/best_hollywood_movie_download_in_hindi_720p.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d2c906f6-1d77-4391-b112-735a6d9096fa/51407919685.pdfIn PDF document text
    • http://nigezid.pbworks.com/f/interpreting_double_bar_graphs_worksheet.pdfIn PDF document text
    • http://gosirata.pbworks.com/w/file/fetch/144452046/hotels_near_me_with_jacuzzi_in_room_nj.pdfIn PDF document text
    • http://nuxawakaxaz.pbworks.com/w/file/fetch/144497052/how_to_cite_the_declaration_of_independence_in_text_mla.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cdc9b643-c10f-4af6-bf13-6e3f4daacbaf/39584336601.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dc786175-a947-46cd-95ef-ad70adda7647/jaxofatebexapifiwutik.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b0a0fb7-12cd-4ced-843f-fe9fc1cd9ba4/jomuneda.pdfIn PDF document text
    • http://lulimogosan.pbworks.com/w/file/fetch/144510108/android_oyun_club_gta_v_cretsiz_indir.pdfIn PDF document text
    • http://pokuwatosat.pbworks.com/w/file/fetch/144556509/descriptive_words_for_music_sounds.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c7342786-c766-4222-affb-d32ebfb1a8b8/sivebumumutere.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e167.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE167 5208 bytes
SHA-256: 07d41790df0031e371a7e742818f22fe2365b21084d9b8dbc4221e5fbd708548
font_01_sfnt_off0000f332.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF332 10408 bytes
SHA-256: cc189b9862efdd8b2fb3763a6672f7bbc26a349a613df43061c60a2f0b570963
font_02_sfnt_off000116f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116F9 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3