Malicious PDF — malware analysis report

Static analysis result for SHA-256 666787cd7c26935e…

MALICIOUS

PDF

81.5 KB Created: 2021-09-14 13:16:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9e80982533660859c16c9e34286a7ddd SHA-1: 83366c593b314baef84977dbe23492297ba92128 SHA-256: 666787cd7c26935ec374abc2ae102d60f9462a74093e7ba77f1d2c5f73bfe318
66 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to PDF files hosted on various domains, indicating a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior. While no scripts were extracted, the ML classifier strongly suggests malicious intent, likely related to redirecting users through a chain of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 4

  • 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://brahmagnanam.org/fck_uploads/file/61004350189.pdf In PDF document text
    • https://drakbera.com/ckeditor/ckfinder/userfiles/files/nakuzale.pdfIn PDF document text
    • http://ukwoodrecycling.com/userfiles/files/43603751510.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/161372413227bd---xaviluzo.pdfIn PDF document text
    • https://phr4u.com/files/9897799765.pdfIn PDF document text
    • http://zkojicin.cz/userfiles/file/pumowaxed.pdfIn PDF document text
    • http://www.espaciocultivarte.com/ckfinder/userfiles/files/12130950172.pdfIn PDF document text
    • https://excellencetogether.com/img/files/file/regepokesasap.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/filivava.pdfIn PDF document text
    • https://volandovia.it/public/fileeditor/file/balizep.pdfIn PDF document text
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/xiwola.pdfIn PDF document text
    • http://schokoladenbrunnen.de/idata/netazovamewanokibikakubed.pdfIn PDF document text
    • http://graylegalservices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/94159726484.pdfIn PDF document text
    • http://konditsionery-zheleznodorozhnyi.ru/upload_picture/file/goxepi.pdfIn PDF document text
    • https://atpl.aero/ckfinder/userfiles/files/deluxukevijapajikuro.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kizanaxebazapanepaloj.pdfIn PDF document text
    • http://kfbma.org/files/fck/file/30706533962.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613acb640d4ee---lugazufunifaval.pdfIn PDF document text
    • http://computerdoki.hu/user/file/93977796368.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/73880266181.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/demozite.pdfIn PDF document text
    • http://veitali.com/upload/files/3789163474.pdfIn PDF document text
    • https://auto826.com/uploads/files/39585079685.pdfIn PDF document text
    • http://bobas24.pl/Upload/file/giwito.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=vaste+song+download+mp4+free+downloadPDF 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_off0000d419.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD419 19532 bytes
SHA-256: 87e0c81eb4da78710b01a2d58f032b84a74dc1c64cc98221d82fd86fdd902ace
font_01_sfnt_off000106c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106C6 10884 bytes
SHA-256: 6316304d0c9cd75cc8bc3471517e137d1a9977f818568058dd5b5cdcf7cec36c
font_02_sfnt_off00011fdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1