Malicious PDF — malware analysis report

Static analysis result for SHA-256 1053c79897ee8a6d…

MALICIOUS

PDF

83.2 KB Created: 2021-09-11 22:59:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 55f9840998430d1b423777891d51a238 SHA-1: 8411833dd295694a546174617efe4ce4d50a523e SHA-256: 1053c79897ee8a6d6c06e8927cfa2cb4e2175f8bd5662c7993ff79fffbd7dac4
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting, suggesting an attempt to obscure the final destination. The ML classifier strongly indicated maliciousness, supporting the conclusion that this PDF is designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://doanandieuduong295doson.vn/namthuan/images/news/files/58310681601.pdf In PDF document text
    • http://phone-server.com/userfiles/file/vubimunewenezo.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/tte02n73gtvvq3iu8v5ccmt0h0/26146850759.pdfIn PDF document text
    • http://safetruck.gr/images/file/rapubaluzinigevulipejiba.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/fesajadogegojepadofavub.pdfIn PDF document text
    • http://to-kajihan.net/js/upload/files/vawadapipasofuruvev.pdfIn PDF document text
    • https://panificioilcavaliere.it/userfiles/files/88103493352.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/161363c3a532f3---vusilora.pdfIn PDF document text
    • http://th-hl.com///upload/files/58518754423.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/bezexafipo.pdfIn PDF document text
    • http://ddgasul.com/userfiles/file/xasaruzope.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/30382237609.pdfIn PDF document text
    • http://maradonasalud.com.ar/ckeditor/ckfinder/userfiles/files/gefozo.pdfIn PDF document text
    • http://santeh.md/img/files/xejufedepoziwuwufenuv.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/zenejopopomodomexunof.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613061b88c851---siweputukuduwofujetizezek.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/5a3154539547cee7035445717b688090/51422678828.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/sqm5ab3hn7nm4f07splsfu5se6/27573789312.pdfIn PDF document text
    • https://reniuved.it/file/gasojaxizomixofazifidiva.pdfIn PDF document text
    • http://www.bargiel.com.pl/ckfinder/userfiles/files/69123243127.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/98428579630.pdfIn PDF document text
    • http://gmtshipping.com/attachment/file/69145012243.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/jofonuvovakovob.pdfIn PDF document text
    • https://shreegroupco.com/userfiles/file/wubozum.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=3juices+mp4+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_off0000de96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f6ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6AD 10948 bytes
SHA-256: 212948f38134b69c1185aee3848f61ad389d83264d7cdbd235496d038847a096
font_02_sfnt_off00011013.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11013 18000 bytes
SHA-256: fd8659bc1d8be4cb6c84c4b2eb1d2ec058fe7738b51931bb38c0c33437db39a2