Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3860303cd4ee8c7…

MALICIOUS

PDF

74.7 KB Created: 2021-06-07 02:50:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 40eeefed4cfae2a2ff8035efbf61f79a SHA-1: ea16adfeef4c59a632577b686a457d4d4cb97970 SHA-256: f3860303cd4ee8c747cd8a4a5f5fa930346b4e2adc8921792fa8b5c8993acdc6
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, likely intended to distribute malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of numerous URLs hosted on various domains indicate a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://medvor.ru/uplcv?utm_term=siren+head+woods+game+download+free
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2f9765fe7---84298088639.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160974775a8d54---sabuwiwamuxuturiv.pdf
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eda516c6ed---45856550968.pdf
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609428771d530---88585549579.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/a854ff8242da6dbd31310d98e6b4d3d6/89132118277.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094b2cf7a46b---28380320729.pdf
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/0256929e0650814a1f7394590b4ea737/35210259018.pdf
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/02f276280ec8c9d0a7348c369111acbe/98692033303.pdf
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/b50c8c451553930bb4131ef58e7668f6/moduseka.pdf
    • http://thaide.org/userfiles/file/84975289215.pdf
    • https://xo-sound.ru/userfiles/file/8434108054.pdf
    • https://hasekei.jp/userfiles/file/68733567796.pdf
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/e97e683322f3ab8909b3c46a24005f25/16962477794.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085fb57e6eb7---38109764761.pdf
    • https://yucekalipmakina.com/tsrm1/img/userfiles/file/93293495828.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/16074273be1a1b---29412036700.pdf
    • https://bodwellassociates.com/wp-content/plugins/super-forms/uploads/php/files/49397058e61b9337ed7cd5c76a479806/nubika.pdf
    • http://jtour.vn/userfiles/file/pevulasawipivasumis.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d7a4.bin
9ba493c9788a34a131b7e40f4ebc5aa8f7b77eef1113dbecbb42b9b842485fb3
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A4 5224 bytes
font_01_sfnt_off0000e934.bin
e63740281c75b54d29b6522f0b4fd370495fe3084739624698720aa2c382e852
pdf-font-stream PDF embedded font (sfnt) at offset 0xE934 11572 bytes
font_02_sfnt_off00010f4b.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F4B 4324 bytes