Malicious PDF — malware analysis report

Static analysis result for SHA-256 33971e47b9b5e9bb…

MALICIOUS

PDF

169.3 KB Created: 2021-05-13 16:01:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 57b9bdd4e16fc338969ee5b17bd8cc93 SHA-1: 3c86566fe0cc7fd65d38c3f1fbb43d849afcf44a SHA-256: 33971e47b9b5e9bbeb46dfcd2de42a581ecd19cf2f8acb66c8e27f3117f8fc0c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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 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/strik?utm_term=himno+al+maestro+boliviano+vocabulario PDF link annotation
    • https://nuruvubapifak.weebly.com/uploads/1/3/1/4/131452890/9620095.pdfIn PDF document text
    • http://sallles.ru/5240146310414qrm.pdfIn PDF document text
    • https://xumogawas.weebly.com/uploads/1/3/5/3/135341739/koserazuwigi-bosufefasikub-rolalam.pdfIn PDF document text
    • https://lasirobazu.weebly.com/uploads/1/3/4/3/134399905/kinikep.pdfIn PDF document text
    • https://durunefa.weebly.com/uploads/1/3/4/7/134712847/sinagugefasa_mebivenusekebuk_purufamiseji.pdfIn PDF document text
    • https://cdn.sqhk.co/vixawutozama/0jdicig/newegg_return_policy_on_refurbished_items.pdfIn PDF document text
    • https://fufukarebalomok.weebly.com/uploads/1/3/4/3/134352968/manowixagijafi-devujaxevav.pdfIn PDF document text
    • http://febanadedej.22web.org/52429388244.pdfIn PDF document text
    • http://dfahsdfgjsfg.online/jamawuzarodiragudojojesezt2ki.pdfIn PDF document text
    • https://cdn.sqhk.co/luwiliziv/Jicmvjc/834308872.pdfIn PDF document text
    • https://vifaniju.weebly.com/uploads/1/3/4/5/134507083/2271018.pdfIn PDF document text
    • https://vazoxavaver.weebly.com/uploads/1/3/4/8/134863882/jesavuvisopat_bapuvapamelovew_pisuwa_dusiwosura.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/viregujipowuru/73090546806.pdfIn PDF document text
    • http://xagewojijakeri.rf.gd/incorporated_business_tax_forms.pdfIn PDF document text
    • http://laxunuwozen.epizy.com/general_science_reviewer_with_answers.pdfIn PDF document text
    • https://s3.amazonaws.com/fixararololu/dilated_coordinates_worksheet_answer_key.pdfIn PDF document text
    • https://s3.amazonaws.com/lawakux/rabipuxotevizi.pdfIn PDF document text
    • http://lusuzajemofim.rf.gd/how_to_use_light_transfer_paper.pdfIn PDF document text
    • https://s3.amazonaws.com/firudegix/xazobozivodijav.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_off00025ebd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25EBD 5108 bytes
SHA-256: 43ec7c9f7556563210f583e34548cfd20ed738a572fe091d6df6c0c850c8e1ee
font_01_sfnt_off00027005.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x27005 11796 bytes
SHA-256: 314da2c74f2ce4b66a4a702b037e0a9bfe48049b27c62aebb050abfa6ba41cf8