Malicious PDF — malware analysis report

Static analysis result for SHA-256 afbf9136fcdc8761…

MALICIOUS

PDF

86.1 KB Created: 2021-09-16 04:01:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6d0c44ceaad8eaed831a2b1c55e4cdf7 SHA-1: 99fef0747b80862d895f8d30796883f573b6233e SHA-256: afbf9136fcdc876156fe457241ba6153749af821322a15ac4cf6ec05f82f9765
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file exhibits characteristics of a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised CMS platforms or disposable hosting. The ML classifier strongly indicates maliciousness. The primary attack pattern involves luring users through a seemingly innocuous document to click on these links, which likely lead to further malicious content or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://espwireless.net/uploads/file/91463707641.pdf In PDF document text
    • http://taihegas.com/filespath/files/20210914005918.pdfIn PDF document text
    • https://tannhatviet.vn/upload/files/1754261505.pdfIn PDF document text
    • http://bestpokeya.com/uploads/files/87501015695.pdfIn PDF document text
    • http://natur-pet.cz/webpagebuilder/ckfinder/userfiles/files/24258241903.pdfIn PDF document text
    • http://losmarinoslanzarote.com/marinarubicon/admin/file/338255900.pdfIn PDF document text
    • https://fishuntpesca.it/file/rugigijajan.pdfIn PDF document text
    • http://wdnederland.nl/file/lidazarisos.pdfIn PDF document text
    • http://natpuedu.in/userfiles/file/pexosazufotixixatanobozej.pdfIn PDF document text
    • http://satyavnetworks.com/fck_upload_images/file/vozaxevijifowoxemivowiko.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5029416e4---jigininubopoba.pdfIn PDF document text
    • http://balone.net/_upload/file///72586094605.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/zevudonal.pdfIn PDF document text
    • http://findmealocalpainter.com/insurazon/admin/userfiles/file/62151154029.pdfIn PDF document text
    • http://wwm-quanta.com/upload/files/nisojetegupewugabix.pdfIn PDF document text
    • https://keyword-lda.pt/site/upload/file/wemifuse.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/sozajaxinizorubotas.pdfIn PDF document text
    • http://depcip.com/app/views/panel/ckfinder/userfiles/files/mexivibe.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1612f8c2291b5f---dugulujiburojejujavo.pdfIn PDF document text
    • https://semineebrasov.ro/printuri-fi/files/busesabixuloj.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613e30c88fe75---84661562801.pdfIn PDF document text
    • http://cochemical.com/upload/files/vuxupeperoferapopofu.pdfIn PDF document text
    • https://asoriofrio.org/ckfinder/userfiles/files/xonanesigemesofe.pdfIn PDF document text
    • https://jurvamartin.com/userfiles/file/pidapaxewuxebunufedubiko.pdfIn PDF document text
    • https://certifiedcollisionrepair.com/home/cert/public_html/ckfinder/userfiles/files/noxapadomibunedopagi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=best+cloud+gaming+apps+for+androidPDF link annotation
    • 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_off0000e994.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE994 18140 bytes
SHA-256: cb19592848c4ee207c793d7bd47853c534df298da0da369e96503ada311db577
font_01_sfnt_off0001183e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1183E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13055 11116 bytes
SHA-256: 49a73dddab5d2a815de2a0ebd2a672aba15bf7dec0c2f94f3add1b371ae42874