Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d81fff3e0775a83…

MALICIOUS

PDF

82.0 KB Created: 2021-03-20 16:09:55 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: a4acc668737dc3c336bec06109a4ce48 SHA-1: b6a24370a39d4c66e0598d40cd87a18b1b1d56f5 SHA-256: 7d81fff3e0775a8391ef876f1f3e78afd8a8fd99544ff341ac65da62f639de60
186 Risk Score

Malware Insights

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

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 0.9993

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=how+to+get+rid+of+water+pimples+on+feet PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4386830/normal_605067a718036.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470828/normal_60315911ab9f6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416136/normal_60190321c8e3f.pdfIn PDF document text
    • https://cdn.sqhk.co/noviraxat/iiDjcgi/93585055360.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4410441/normal_5fde0f7128661.pdfIn PDF document text
    • https://cdn.sqhk.co/jumifokujuje/jhjcghm/jefutikekovikamisi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371807/normal_6040fbfd15c5b.pdfIn PDF document text
    • https://cdn.sqhk.co/xexanodu/c4ifuie/pokemon_heartgold_download_nds_zip.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4428334/normal_604334fd0616d.pdfIn PDF document text
    • https://cdn.sqhk.co/dibirolinu/NgdG2je/mupewoxedotunovoso.pdfIn PDF document text
    • https://cdn.sqhk.co/lowovegoxoji/gqxhcQf/couple_love_baby_images_free.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4420767/normal_5fcc4438efc6d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4489740/normal_5fceb1ed49c84.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373520/normal_604d27bc1c0f0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417128/normal_5fd9425ca498e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://luzutajezilako.rf.gd/english_grammar_for_dummies_1st_edition.pdfIn PDF document text
    • http://ludesol.rf.gd/allahabad_university_msc_admission_form_2018.pdfIn PDF document text
    • http://lijezuzoxej.epizy.com/kinsey_reports_quizlet.pdfIn PDF document text
    • https://18aefb47-0221-41c7-ace0-4f78eb33e730.filesusr.com/ugd/bca722_12fc2e0d6b0b4bdc9db2491f64daac3c.pdf?index=trueIn PDF document text
    • https://9db8f275-5044-409a-aa1b-3306d9dda9bd.filesusr.com/ugd/361f4b_4768990ed8f546288c6ed544f814e66e.pdf?index=trueIn PDF document text
    • http://zozozixub.rf.gd/tamilrockers_hd_2018_movies_free.pdfIn PDF document text
    • https://c370dac7-4848-4fa0-a6df-94361299e8ba.filesusr.com/ugd/fa6303_a38d68012e8c4c5881c21808750e2980.pdf?index=trueIn PDF document text
    • http://xoponupesede.epizy.com/principles_of_microeconomics_7th_edition_mankiw.pdfIn PDF document text
    • https://52b03d57-94e3-497b-b2ee-5a576b8f136c.filesusr.com/ugd/67ae49_a34f189f1cde44f9a8ce8dbf214a27be.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_off000101cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101CF 5416 bytes
SHA-256: 2e1a616d7279c0941f9abbcf17329181ea2ab0f323def8c4cd88d6061ec3ee0f
font_01_sfnt_off0001143c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1143C 11196 bytes
SHA-256: 2516133a7bd38b14c7e1e49417eebd6f9e762c2cb974f69a7bd0588d799d9bdc