Malicious PDF — malware analysis report

Static analysis result for SHA-256 9ff768ec1659684a…

MALICIOUS

PDF

80.0 KB Created: 2021-05-07 20:13:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 4f7e9751f0c0564cfcfacc5d9c36f660 SHA-1: bd13d957e19354e957e29e1539e19bd346700d5c SHA-256: 9ff768ec1659684a0bef52a6f290aeba8bf28c2084587d460242bf4d4ccaf902
244 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a redirector link and a large link farm on disposable hosting. The ML classifier and ClamAV also strongly indicated maliciousness. The embedded content, though heavily obfuscated, likely serves to host these numerous links, aiming to lure users to potentially malicious sites, consistent with phishing or spam campaigns.

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/strik?utm_term=jaycee+dugard+book+excerpt In PDF document text
    • https://lukumupanulafaz.weebly.com/uploads/1/3/4/6/134683212/vorisopepetod_gubog.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384037/normal_60546df505414.pdfIn PDF document text
    • https://dapazigozasonim.weebly.com/uploads/1/3/4/4/134466252/38fe062d161e.pdfIn PDF document text
    • http://dimopun.mywebcommunity.org/alkaline_phosphatase_in_pregnancy.pdfIn PDF document text
    • https://banepopewux.weebly.com/uploads/1/3/4/2/134234854/dasoxid.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4402717/normal_5fed3cff7196f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384460/normal_602c0cb608ebc.pdfIn PDF document text
    • http://majusenise.sportsontheweb.net/5_point_hedonic_scale.pdfIn PDF document text
    • https://kabijibijeg.weebly.com/uploads/1/3/4/9/134900291/d1190.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478961/normal_60561d48a270c.pdfIn PDF document text
    • https://muvusawit.weebly.com/uploads/1/3/5/3/135392745/dugupufiwatutuzumog.pdfIn PDF document text
    • http://fafuzum.sportsontheweb.net/how_to_charge_a_nano_ipod.pdfIn PDF document text
    • http://tixanijematewe.mypressonline.com/58515215053.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370278/normal_604048664368a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/jagux/69499134772.pdfIn PDF document text
    • https://s3.amazonaws.com/fisulefajow/wiroxadivoporuvewagus.pdfIn PDF document text
    • https://s3.amazonaws.com/nafamaragisek/measure_theory_books_free_download.pdfIn PDF document text
    • https://59e5a08b-0d8d-455f-a3a7-35a3b781ab3e.filesusr.com/ugd/784815_df3d743e89084ebe9a7539d1dd58c8b2.pdf?index=trueIn PDF document text
    • https://c9b0c9dc-51ad-46ec-84b2-dbc26df53712.filesusr.com/ugd/b6f588_cf7c771a2915451dbd14c7cb14325bd7.pdf?index=trueIn PDF document text
    • https://27dd58ca-3bab-4825-b0a2-cb75a9f796de.filesusr.com/ugd/aba4c5_7cacd0f3ad874435b21a64fe96cc090c.pdf?index=trueIn PDF document text
    • http://jozilaro.atwebpages.com/agile_software_development_robert_c_martin.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_off0000f8d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D0 5396 bytes
SHA-256: 69523683f87f7616901baa4cfdcf75ffdcc8c8753c4aceda2595ab0a5a8d3f91
font_01_sfnt_off00010b44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B44 11100 bytes
SHA-256: 7ad191c93736ed59b7012c7cd7ad7d9db4eeaf70a5444e85b864596310a321db