Malicious PDF — malware analysis report

Static analysis result for SHA-256 67f0bfcad9544675…

MALICIOUS

PDF

77.1 KB Created: 2021-05-04 08:02:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 6ee9bc700650d458745df80cf511d3f7 SHA-1: 225e5729299d488c0a6885a8fb4a624e94cf2c26 SHA-256: 67f0bfcad9544675b2ef995fab9bc93c2c2238aaf87e52e07944dd3ad8afc4a2
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO manipulation tactic. The primary URL, `https://zajinet.ru/strik?utm_term=elements+compounds+and+mixtures+poem+worksheet+answers`, is presented in a context that mimics a worksheet answer key. While no scripts were explicitly extracted, the heuristic firings indicate the PDF is designed to redirect users to a network of external sites, likely for phishing or ad fraud purposes.

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://zajinet.ru/strik?utm_term=elements+compounds+and+mixtures+poem+worksheet+answers PDF link annotation
    • https://cdn.sqhk.co/mitukutowum/iTgijjN/korean_kpop_video_songs_free_download.pdfIn PDF document text
    • https://lajisoxe.weebly.com/uploads/1/3/4/4/134435468/27a9c99c.pdfIn PDF document text
    • https://duvugatezema.weebly.com/uploads/1/3/4/6/134650783/38dd9.pdfIn PDF document text
    • https://resezavurafufok.weebly.com/uploads/1/3/1/4/131407395/wemozudogopi.pdfIn PDF document text
    • https://cdn.sqhk.co/valujoper/4Co5hjC/bazidipubiwosusugonimix.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4458124/normal_5fed0883ac400.pdfIn PDF document text
    • https://cdn.sqhk.co/mapetidul/ji4hejf/57830747517.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4505837/normal_604bc5ebdabeb.pdfIn PDF document text
    • https://cdn.sqhk.co/fojoravuvu/gdjjPjg/nunovuzajagodavujon.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373281/normal_5fe8cbe080727.pdfIn PDF document text
    • https://cdn.sqhk.co/tatidukigag/hagdidm/64308510573.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488569/normal_6039ccfa0deba.pdfIn PDF document text
    • https://cdn.sqhk.co/womawuxinuge/SicjjCz/entrepreneurship_and_business_management_n5_book.pdfIn PDF document text
    • https://cdn.sqhk.co/jufebarur/hiheiiz/account_balance_sheet_moneycontrol.pdfIn PDF document text
    • https://cdn.sqhk.co/gudijupimeb/b3ijicI/minecraft_pe_skyblock_seed_2020.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4fe85328-8dbf-40e9-afa8-2c8d6ff8a9c8.filesusr.com/ugd/9c0842_e15ea5b86fcd48399430cdef8f1d1add.pdf?index=trueIn PDF document text
    • https://9df6fdd8-df71-43fb-87ad-b121b2de7416.filesusr.com/ugd/e0d0cf_1300c4f8cb3e4111bf0225cb5bbf3829.pdf?index=trueIn PDF document text
    • https://4eb3a9b5-ca6a-4b2a-896e-878abc754f3b.filesusr.com/ugd/f1ab86_78c0d652212f4043a98e655b8a8d5146.pdf?index=trueIn PDF document text
    • https://4cf2acc4-d143-4013-a78d-f21de0873c4f.filesusr.com/ugd/e4636f_9cfc244a4ce94111b186955a977a2be7.pdf?index=trueIn PDF document text
    • https://e966359d-176b-477a-9ad9-c314bea94227.filesusr.com/ugd/fa6f14_e51a483c3a4f4d0d8bcf1ffcd5934c51.pdf?index=trueIn PDF document text
    • https://7e70056c-c2aa-4e53-98c5-50750123c107.filesusr.com/ugd/f8ae5d_f65d661e12da41e39eaece1c057fdab9.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_off0000edde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDDE 5496 bytes
SHA-256: 236188dc123a9407fbdae336ccfe8b50bfdc873694612f9dfb14ed7a6f6d667d
font_01_sfnt_off0001007b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1007B 11260 bytes
SHA-256: eb7afb1c6757af15202b2bcd265968e38843376c8b6529ee43660eb5471aff7f