Malicious PDF — malware analysis report

Static analysis result for SHA-256 5208aac3e9c97558…

MALICIOUS

PDF

98.2 KB Created: 2021-06-21 15:27:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 395b3d21ca59e9dc4d1235b03e08df8a SHA-1: 1aecfaf9a968ead91c067b6863924cf7cac8b754 SHA-256: 5208aac3e9c97558bbd72cbe3211e246946665cb454d6183ce1568d9c5b06ac4
112 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

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, presents a deceptive download button and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://chcial.ru/uplcv?utm_term=nelson+biology+11+textbook+pdf PDF link annotation
    • http://www.hangmandigital.com/files/file/kufokexaluripu.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd5585f9b6---buserarufase.pdfIn PDF document text
    • https://kodcomputers.ro/2664/uploads/ropitisifegiruzil.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/ob43jnbc5voav4hu8k3h0pj3dj/sigivufodavovevuxunebilav.pdfIn PDF document text
    • https://www.lightingsolutionsal.com/wp-content/plugins/super-forms/uploads/php/files/92a4daf35b4bd5c94bdaf57528642ced/mirebuganasu.pdfIn PDF document text
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bfbcd013ec---73746899160.pdfIn PDF document text
    • https://albawadiroad.com/userfiles/files/givamanumox.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/e28c2ce08a90b75e81ea0ca7037af6a0/ginakeluvos.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/93948967164.pdfIn PDF document text
    • http://volvo-cars.jp/js/upload/files/22495644256.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/6qffc2n3h381r2jj9caki5kh4l/golezuvigopawoxata.pdfIn PDF document text
    • http://www.ochoadentalcare.com/tacgestorcontenidos_ochoa/documentos/file/53541610897.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bb058f5b4a0---dirajepewefuba.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16075159c82a72---pisapejita.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4d8816a7c9---digewuxeruz.pdfIn PDF document text
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a287a9f11e4---35215454925.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000142cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142CF 5296 bytes
SHA-256: b6a1eb923b3cd412d29f5c50a6ea99246522d261d9a2ae1cbfc54318a4460b75
font_01_sfnt_off00015504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15504 11340 bytes
SHA-256: 515b0748ca80e4bb16c911433cdfc4fed9bbf0a90660f02f48dc8b893a5aefa1