Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce337552cfcbe287…

MALICIOUS

PDF

75.6 KB Created: 2021-09-06 11:25:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 9ebe4979e8de00685f4b063e724f8001 SHA-1: 3767858ee8203003104c87d8c360a7d2b5111cee SHA-256: ce337552cfcbe2870a78534648cf73d25aed01d9f2f2419d87b6a68be9fd2021
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or are hosted on disposable domains, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights this behavior, suggesting the document's primary purpose is to distribute malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://philabc.ru/uplcv?utm_term=12th+economic+tamil+medium+book+pdf PDF link annotation
    • http://cuatro-pr.org/sites/default/files/file/xafuner.pdfIn PDF document text
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kuxowi.pdfIn PDF document text
    • http://eros-arena.com/eros/userfiles/file/84015025223.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/xikosixenupotefove.pdfIn PDF document text
    • http://csc-0411.com/userfiles/file/20210818073331_324p2e.pdfIn PDF document text
    • http://as-eng.biz/userfiles/file/52407830753.pdfIn PDF document text
    • https://pediatricpotentialsnj.com/PP/PPpng/files/fokenevomo.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/josutagifos.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1609d1b56c6d72---wuvunipifolejudajogo.pdfIn PDF document text
    • https://mayersoffice.com/userfiles/file/loketaramegaralu.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/161168fbcb900e---sevomigexijuza.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3f04a87e9---mizeroxanumi.pdfIn PDF document text
    • https://nwdglobal.com/ckfinder/userfiles/files/nenegarozunurotufa.pdfIn PDF document text
    • http://aucoindeshalles.com/menu/file/43630610448.pdfIn PDF document text
    • http://yogo110.com/userfiles/file/napuwoketi.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f75709add0---19614294103.pdfIn PDF document text
    • http://farashimirooz.com/files/30084231589.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/qdtbes03ia25urqmsukm8jbi12/58233023333.pdfIn PDF document text
    • https://bankubezpieczen.pl/userfiles/file/4319679253.pdfIn PDF document text
    • http://laihoawedding.com/app/webroot/upload/files/76697643173.pdfIn PDF document text
    • https://edusfera.pl/upload/file/14511111258.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/34634577450.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/62eb77e0c17c981200e5aadb55a58f6f/nediwopu.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bb60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB60 11024 bytes
SHA-256: 4b888e2d72b4f790159823f479bf966214047803dbef15d5ca0bcb7c298e587e
font_01_sfnt_off0000d49a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD49A 19824 bytes
SHA-256: 70895411f539e5306d7e5c43d3995196fbfb01e0a2a5425e178ed48b4a717d18
font_02_sfnt_off000106f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1