Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f12b7cbc38d7bad…

MALICIOUS

PDF

127.5 KB Created: 2021-06-11 07:57:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: dcb6a612dc8410501373108bfa43d486 SHA-1: 99c2f514ab2084d84d65b83869e0dbb0b0757a3c SHA-256: 6f12b7cbc38d7bad8e45259c7ca9c012425322f2314beb85d68ccc1a1f0c04e3
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://irlanc.ru/uplcv?utm_term=skam+nl+season+3+episode+1 PDF link annotation
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acd7b45c861---kewipidomisufuvo.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/8rk2nsdqvpjvbbgvfacb7jg7hg/7715915103.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/95399693051.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16083b59ed90f7---14561183954.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/a1af12dc9d154f75a42b0e17d8b79b12/xowog.pdfIn PDF document text
    • http://edu-mate.kr/_UploadFile/Images/file/85475297015.pdfIn PDF document text
    • http://abogarestudio.com/userfiles/file/subinubiresuvewimosilusoj.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b82bd610a6e---35736277066.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073b505c2560---vuwefuseg.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160731cdbbc5ab---31508050862.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/19h71rvm2ma7ole5akklvbocg6/29483916980.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/350f4a2c59b8a713a852e58a40330568/rarixifaperepewetuvulosar.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/756e57a80fba85d9a90213a8d7f49594/80969486565.pdfIn PDF document text
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/c5d54dc2f8d201455380b169d8a9367e/19025641830.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a01f1262553---gikop.pdfIn PDF document text
    • http://shosholoza.de/file/dopobeborudodiwetugokek.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/16073a66c06197---39679329281.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607cca466dd58---zimozo.pdfIn PDF document text
    • https://www.latentoac.com/portal/wp-content/plugins/super-forms/uploads/php/files/bjuktb93f00i4g5hnosph0a9p3/wilixevebuvifovirekoleri.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/66136423106.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://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_off0001a623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A623 5100 bytes
SHA-256: 12ce11db7648ebe94070bda5273178cdd76497babc5b6fc6c61e9b46b73f303c
font_01_sfnt_off0001b754.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B754 14096 bytes
SHA-256: 7594d52c3e2b02e16644bae99a0b97c94b06b98e35e154637722e01150f5a0fe
font_02_sfnt_off0001e231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E231 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f