Malicious PDF — malware analysis report

Static analysis result for SHA-256 84cf15212d56fae1…

MALICIOUS

PDF

89.8 KB Created: 2021-07-14 06:07:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2e43666b63dfc080d1a6694d9708ef57 SHA-1: 7d0387a38d0f3c3e6b665bee472ca201d46cb5f1 SHA-256: 84cf15212d56fae1fd64f931cdfb7a4dbd7c5739a2d0a070bd652a4f03acb30c
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external URIs and links to compromised WordPress sites, indicating it functions as a link farm. The ML classifier strongly flagged this PDF as malicious, and the heuristics suggest it's designed to redirect users to potentially harmful content. The document body is heavily obfuscated and unreadable, providing no further context on its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 5

  • 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://archism.ru/uplcv?utm_term=mediation+in+conflict+resolution+pdf PDF link annotation
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/da5c78b288e5b52b48106d9187fd38b3/90941078204.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160a026351e554---41283912971.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/a8405f60d152df64df3e79c5bd27105f/tesupisid.pdfIn PDF document text
    • http://allaboutdowney.com/userimages/13266646826.pdfIn PDF document text
    • http://churchillreunion.com/clients/72216/File/49504833552.pdfIn PDF document text
    • https://anpheatingandac.com/nbloom/fckuploads/file/lejizefepugamilanan.pdfIn PDF document text
    • http://hotelborgodeipoeti.com/userfiles/files/fewalawivuzamojiv.pdfIn PDF document text
    • https://detmers-kontejner.hr/files/75150224170.pdfIn PDF document text
    • https://avgdesign.com/userfiles/file/99860999635.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acad12234e5---42304773283.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160879406a78f9---60606902798.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/37315263919.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/romubagifuvosuroz.pdfIn PDF document text
    • http://aivieksteslaivas.lv/userfiles/file/9380734160.pdfIn PDF document text
    • https://keralahappyjourney.com/ckfinder/userfiles/files/25146820223.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/893406843feedc2d9e6b56c307b517e6/jusukubumefemejojexi.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/8350a5bb124392aee3e3c772bfe036e3/42296936702.pdfIn PDF document text
    • https://condominiobrisasdelnorte.com/userfiles/file/29647456368.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5cba18d23---ropepojunivokusape.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089db62a6254---sogegoguraxov.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/d0140ad9f478f8eea4bf343d2ad8dc68/81836671255.pdfIn 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://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_off0000fd5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5C 10704 bytes
SHA-256: 43b269b4bc0538ad660e3f6ce5b36388e177b4782d91bfe0943a07559910e68f
font_01_sfnt_off00011609.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11609 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012e1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E1B 17080 bytes
SHA-256: 52ae5c01384e100fee80bcf028ef44880b18e4b5536c5f6a7e4517c4fb956155