Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb5430bc914d972a…

MALICIOUS

PDF

111.2 KB Created: 2021-05-16 13:14:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a842dd944f23a7590adc45cabdd7d4d3 SHA-1: 3806e0b8470b87832685c08515f868345d1410c9 SHA-256: fb5430bc914d972a8de2f994b316695c23ecd5132b77ad63f0877ec5048d0f95
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to potentially malicious or phishing websites. One prominent URL identified is https://vilenefex.ru/strik?utm_term=dengeki+bunko+fighting+climax+pc+download+free. The presence of embedded JavaScript, though not fully analyzed due to obfuscation, further supports the malicious intent of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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 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=dengeki+bunko+fighting+climax+pc+download+free
    • https://namevixezevir.weebly.com/uploads/1/3/0/9/130969021/zijunajeva.pdf
    • https://muvuvudu.weebly.com/uploads/1/3/5/3/135351086/d4cf76ac.pdf
    • https://dojoxokixen.weebly.com/uploads/1/3/4/8/134878929/tavuvuwej.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://vidugozu.atwebpages.com/anti_apartheid_movement_in_britain_and_ireland.pdf
    • https://s3.amazonaws.com/winumigutam/hp_deskjet_5610_ink.pdf
    • https://e42ce0b3-f376-4cb5-9abe-507fdbb9570c.filesusr.com/ugd/603474_001db11d301c476fb98196d389cfe196.pdf?index=true
    • https://s3.amazonaws.com/pisedij/34460885133.pdf
    • https://7915398d-c9c2-4241-abdb-40cf742e4b8d.filesusr.com/ugd/d4df0f_e2acd4723ca5491d925530755b24f92e.pdf?index=true
    • https://uploads.strikinglycdn.com/files/a2749e59-e43e-472c-ba9e-1b8ee4a0f83d/financing_balance_sheet_meaning.pdf
    • https://0fecb50d-c8db-4b5c-a67e-01a13b1c0e9a.filesusr.com/ugd/da7c2d_13eb3f4c53e74fe59866fd5be28111d6.pdf?index=true
    • https://d86ad34a-7df2-4f47-937b-a12ab5abc0fa.filesusr.com/ugd/8cbfce_1360eadfab404635ad2f1dfe01e4b117.pdf?index=true
    • https://235a1a37-2bc9-4d3b-8f1d-d3952ad9fba8.filesusr.com/ugd/3111f7_fe1d9e2bd03d44768565c5a53d295cbf.pdf?index=true
    • https://59b7e61f-9850-45ee-add2-e9646db267e4.filesusr.com/ugd/5b9365_d08fbfe17300475bb16a016a970770f9.pdf?index=true
    • https://a146b927-ed54-472d-b3a8-6b137e313b92.filesusr.com/ugd/4d400c_d8ce0d10c4af4f9992cddbe17b70623d.pdf?index=true
    • https://uploads.strikinglycdn.com/files/da7cafe0-a58f-4fb5-846a-8ef337fd0ff9/38069673208.pdf
    • http://pimobepetokonud.myartsonline.com/75516634423.pdf
    • https://s3.amazonaws.com/nitajosasa/nasb_bible_app_iphone_free.pdf
    • https://s3.amazonaws.com/fazujo/metformin_starting_dose_pcos.pdf
    • https://uploads.strikinglycdn.com/files/420fe3f3-5b1c-473f-9df5-dbb757a080d1/13919176159.pdf
    • https://uploads.strikinglycdn.com/files/7f98ed39-5d4f-4361-95c8-82820f12e231/line_6_hd500x_power_supply.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000105eb.bin
968dc711784efde470bf4603a1d31ae411fa360bbd4d0e8095f0f22cf61d65a1
pdf-font-stream PDF embedded font (sfnt) at offset 0x105EB 35276 bytes
font_01_sfnt_off000173af.bin
bb8a3e1f196faaebbce460a7f590aa40e818314a076eb545cfbed7ad34f32001
pdf-font-stream PDF embedded font (sfnt) at offset 0x173AF 5756 bytes
font_02_sfnt_off0001873d.bin
b278e5301dd33dac024b9e106a21b1ed435368161d02da7868666636dcf1ad92
pdf-font-stream PDF embedded font (sfnt) at offset 0x1873D 11300 bytes