Malicious PDF — malware analysis report

Static analysis result for SHA-256 db7324092c006423…

MALICIOUS

PDF

84.4 KB Created: 2021-09-08 15:02:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0b3a09d2e57a3bfa057b3457177be341 SHA-1: 307851aaa96910b0b9238567573417073a392922 SHA-256: db7324092c0064231ee825dd403d4c285655e1bf59539b21f319de459c2c10e4
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, suggesting a link farm designed to redirect users. The ML classifier strongly indicated maliciousness. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution scheme, likely using the document as a lure for users seeking PDF readers.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://cructi.ru/uplcv?utm_term=pdf+reader+ohne+play+store PDF link annotation
    • http://4bx.pl/public/file/58959362072.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/zokamamigetawum.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/e80a6ca4c9575ffbebece81502683b92/libifevuri.pdfIn PDF document text
    • https://tomclarkvoiceovers.com/userfiles/files/56738265750.pdfIn PDF document text
    • https://ekinyalitim.com/depo/sayfaresim/file/18604702606.pdfIn PDF document text
    • http://marcobernini.it/userfiles/files/93802634736.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/rarokofifulozup.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/ik67t5ke52a0dihtosp3haj3a1/tufivetonebez.pdfIn PDF document text
    • http://www.louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/papilatoli.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16136c626929f9---jojelune.pdfIn PDF document text
    • http://airmon.hu/images/files/89424015094.pdfIn PDF document text
    • http://portalinmobiliario24.com/uploades/fckeditorfile/mifajojamujimuj.pdfIn PDF document text
    • http://xn--b1afklwjc5g.xn--p1ai/ckfinder/userfiles/files/paremil.pdfIn PDF document text
    • http://patanjali.zohukum.com/ckfinder/userfiles/files/81433133976.pdfIn PDF document text
    • http://thefarmatarapahoecounty.com/userimages/32675451464.pdfIn PDF document text
    • https://bruceautoservice.com/files/file/pugemupejeselunufamo.pdfIn PDF document text
    • https://hongmao.tw/uploads/files/202109070006349690.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161361dcc3687c---82969488353.pdfIn PDF document text
    • http://soleilboo.com/images/uploads/files/ketefevuwutosamunavis.pdfIn PDF document text
    • http://isvpro.com/custom/files/bibajedutomul.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/4igs190n1fnj5n2o7blva4809e/medizaxixokosubu.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/1869585378.pdfIn PDF document text
    • http://bajajsports.com/userfiles/file/93460240984.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_off0000e5ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDCC 17772 bytes
SHA-256: f4b1d4a9a88a7917c5c03b32eac09dbc49d53b126ac6505217dadd5da922efd0
font_02_sfnt_off00012b93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B93 10620 bytes
SHA-256: 87761084aefe824671355730edd476a7ff1a82c2ddf44bc1f74b546ba4c2a1b1