Malicious PDF — malware analysis report

Static analysis result for SHA-256 9ef87d9fb91d0e0f…

MALICIOUS

PDF

100.5 KB Created: 2021-03-18 02:06:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: c56ca88475be4af5c37b180bc5cdb3c8 SHA-1: 48da96ff09dbda2275ac5e30f399ab31d24c1f75 SHA-256: 9ef87d9fb91d0e0f376f022505d1cf35967f5dbe5fa5f7cb08a9e01ed8bc6791
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 pointing to disposable hosting, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to potentially malicious content, possibly for ad fraud or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://seumenha.ru/strik?utm_term=vampire+diaries+name+characters+quiz PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4481072/normal_601acc9caf1d9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454545/normal_600ba5a370528.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4529024/normal_604b9c96095ad.pdfIn PDF document text
    • https://cdn.sqhk.co/putizimetiwe/hfr696d/41067036884.pdfIn PDF document text
    • https://cdn.sqhk.co/redupalulaxo/ej5gjWo/82986406223.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407788/normal_602579fce0fa3.pdfIn PDF document text
    • https://pevunefimexog.weebly.com/uploads/1/3/1/0/131070247/dubagakodu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480142/normal_5fdffd2f04115.pdfIn PDF document text
    • https://cdn.sqhk.co/xovujiroveg/4hdUDia/horse_game_pc_2000s.pdfIn PDF document text
    • https://cdn.sqhk.co/dilizilozok/huhcqhd/93862989664.pdfIn PDF document text
    • https://lobekopaxukibo.weebly.com/uploads/1/3/1/4/131453735/zajafetapekadadego.pdfIn PDF document text
    • http://gexedufez.22web.org/26501204562.pdfIn PDF document text
    • https://lemapola.weebly.com/uploads/1/3/1/4/131407815/pajigubebu.pdfIn PDF document text
    • https://cdn.sqhk.co/kukisigafumi/cwjaFig/mastermind_game_2_player.pdfIn PDF document text
    • https://cdn.sqhk.co/wejideduv/hg2hjcH/kunagufezi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422894/normal_6049f03f16960.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454425/normal_60190ab79af6e.pdfIn PDF document text
    • http://moderivapotilos.22web.org/limerumekabegumepajis.pdfIn PDF document text
    • https://cdn.sqhk.co/xewafazuk/nN1Gjhf/38815274359.pdfIn PDF document text
    • https://cdn.sqhk.co/lajagika/jajiijX/muxasi.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
    • http://memaded.epizy.com/sabic_injection_molding_processing_guide.pdfIn PDF document text
    • http://lovemogifad.epizy.com/irobot_roomba_e5_5150_wi-fi.pdfIn PDF document text
    • http://vurasoda.rf.gd/adverbs_of_frequency_worksheets_for_beginners.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_off00013f0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F0B 5196 bytes
SHA-256: b47c82c7405d896b021661d5d3904b1909d1f5b21bdd4a1c9a33e9c5e8db16da
font_01_sfnt_off00015087.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15087 11260 bytes
SHA-256: 3feb9ca68caaf009cc2e3b97e65c7cfc0dd10e6cff99665ab6c8dd463aa671cb
font_02_sfnt_off00017655.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17655 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f