Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d1864bf164643a5…

MALICIOUS

PDF

80.2 KB Created: 2021-07-01 12:18:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 8ffe9cf944c2e814db8eba112d779c6c SHA-1: 0d80c638576cb08fc1922d11074a5ed70d1977f1 SHA-256: 8d1864bf164643a55ca5e932a94bad6f42fa60fc5592bcdf9a695d5a02778a3d
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to compromised WordPress sites. These sites host other PDF files, suggesting a multi-stage attack or a phishing campaign. The ML classifier strongly indicated maliciousness, and the link farm heuristic confirms the suspicious nature of the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160bd984fcdd95---72298367343.pdf In PDF document text
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/9gd5ci6c2gcfh09db54v5qjj84/72927154188.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a32d2a4f50e---kulerisagefa.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160929d8e24dcb---8969832534.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/0531662c312af626e4f8fe63ca0e98c7/pozisonagojovoz.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982f8068374---91286253279.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/2ooesjetjv9c0ftrc27j2dhlt6/xarume.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c46860f0b4---55307460994.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160988c07e1b95---rasigobudole.pdfIn PDF document text
    • http://foodchemsino.com/d/files/1513036570.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082704b3eac3---luvuvimipexituzuti.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/ccc16c10ce2aaeefb843a898bd4fe5a2/10751816137.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/0b01b5b0667314a74621c7e8db9f7e05/79025661946.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/f27bbf1689332fa519dc8673ae287766/kegezupolupakaxugur.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/05847f06879848aab6ba85f065d89082/33919152781.pdfIn PDF document text
    • http://cohensevents.com/clients/74638/File/kunemorat.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16081ba0013d10---90083507905.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/jesaruwi.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16090edfaad503---86013722221.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160799137bab05---razufewukizavaziput.pdfIn PDF document text
    • http://axiomestates.com/userfiles/file/makuwifusuzufenina.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/200feb60be6247d3df92fa647cef1b34/2737218551.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=recycle+copper+wire+near+mePDF 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_off0000d89b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD89B 10512 bytes
SHA-256: 8ecaf71ca154d0b6688ab7ad9f2f81691e1cb483109523201bda60f6fc8516e9
font_01_sfnt_off0000f08a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001089c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1089C 16512 bytes
SHA-256: 2084dc3654383029a0094f7634ea374e45e123c13ae2d73de7f9c8c4cf0a86fd