Malicious PDF — malware analysis report

Static analysis result for SHA-256 c991e493fa0d984e…

MALICIOUS

PDF

83.9 KB Created: 2021-06-13 17:09:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: e494989cd7eb22db7b2a8cfe9d0a952b SHA-1: c3dbe4e7ef6854db41c96052b0661d82ab8d0643 SHA-256: c991e493fa0d984ebedaf3d382e73c932e31b1fd3088066a893cfbb664768bae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution lure. The ML classifier and ClamAV detection strongly indicate malicious intent. The file's structure as a link farm on potentially disposable hosting further supports its use in malicious campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=smart+goal+quiz+pdf PDF link annotation
    • http://agendatourvietnam.com/hinhanh/file/xorenave.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/v2k3m1vg4o801belc8mhsa8pn3/ziroxofipojadujijod.pdfIn PDF document text
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/d2d3ca9b07f4fdb04a54c8c0b91200f0/vozefemewomasenenixufuto.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/6ku3bssb5sfagtru5nklcl2ihb/13881029245.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c5cac8fc7---92918861677.pdfIn PDF document text
    • https://hostingyuvasi.com/calisma2/files/uploads/16810144007.pdfIn PDF document text
    • https://hglobaltourb2c.com/FileData/ckfinder/files/20210613_3A5D7D9822FACF03.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/aoc99981eesuq7r3lic2nj7ec5/norugeximut.pdfIn PDF document text
    • http://keacg.com/upload/files/xixode.pdfIn PDF document text
    • http://www.retorika-zidar.si/ckfinder/ckeditor_uploaded_files/files/sirul.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160814409ca126---27696200044.pdfIn PDF document text
    • http://ehsclassof64.com/clients/b/bf/bfa5c4411462ceee4a19e543862d902c/File/7927796102.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8f5a792ce---natelag.pdfIn PDF document text
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/528f3e86d6eebb435a9ebb03ccb518f8/remerupabisewitajubile.pdfIn PDF document text
    • http://sartor.ru/upload/files/28685967105.pdfIn PDF document text
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec9dc27b86---73933485391.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/e0f8ed8660c9e641783c7e512227d62d/fadilisusemixutufupixo.pdfIn PDF document text
    • https://daleel.global/wp-content/plugins/super-forms/uploads/php/files/4pd04hfnj4jvpne498fmub2poh/mepomuxazevup.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_off00010b2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2D 5464 bytes
SHA-256: 724e9298b893e86220a4689103c6448071cd1b41e81a6ab854f18ec014bdb33e
font_01_sfnt_off00011da5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DA5 11188 bytes
SHA-256: f3e12a7dcfcd5262b468f6a5c5475166fb49fedd211377bd0f42f0ea29066a72