Malicious PDF — malware analysis report

Static analysis result for SHA-256 765a34a48824f20b…

MALICIOUS

PDF

85.3 KB Created: 2021-07-18 17:42:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2e0f18317048929aed8322d4b98339b6 SHA-1: 4d74e39be07fe56ce2df16726c2435ae760c0929 SHA-256: 765a34a48824f20bda295d7ef5c194c10bd0fefd6548316f3a47fac08f901e4e
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting. This suggests the document is designed to act as a link farm, potentially for SEO manipulation or to distribute further malicious content. The ML classifier strongly indicated maliciousness, and the structure aligns with techniques used to obscure malicious intent through numerous redirects and compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://k1a.ru/images/files/file/89941569382.pdf In PDF document text
    • https://locoffice.ru/userfiles/file/78764166537.pdfIn PDF document text
    • http://montazerangroup.com/uploader/file/32512761021.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/24276912605.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606efcce78d13---71961351893.pdfIn PDF document text
    • https://sunrise-photon.com/upfiles/editor/files/musigazigugufot.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160bb719270466---26404213218.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/c26e065f9c60ff9b6710d2c6ffe0d524/27718713303.pdfIn PDF document text
    • https://anfauglir.com/images/file/95523496274.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/1rcilk8bfmb5pph22q8l35c0hb/pirenix.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/42184093422.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/23686562858.pdfIn PDF document text
    • http://harryreichert.de/uploaded_pics/News/file/popaxigasago.pdfIn PDF document text
    • http://mcutech.net/upload/2021/07/file/1625526163124279555.pdfIn PDF document text
    • http://creative-format.com/upload/editor/files/42626565757.pdfIn PDF document text
    • https://residenciasanamaro.es/userfiles/files/ninurobixakulotopemin.pdfIn PDF document text
    • http://rheumatology.institute/upload/content/file/13188366519.pdfIn PDF document text
    • http://k-souz.com/userfiles/file/zexasorotoretop.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/3cb968e7e6b4db86818ae781e805e926/kemimodemokijopokuse.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609845a4d3b5b---33950580345.pdfIn PDF document text
    • http://plncse.hu/php_data/file/45417236549.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/59d66104aa2d02017f32358d58b5e6f9/fegewagufidimirof.pdfIn PDF document text
    • https://www.sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609c44dcd7165---98008722788.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8d64dbdefe---3358614349.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160725b6360dfc---lozozuwedojikobevawiros.pdfIn PDF document text
    • http://libertyquad72.fr/userfiles/file/82769660511.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=three+child+rule+hysterectomyPDF 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_off0000eb6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB6D 10548 bytes
SHA-256: ff1bf6732e75cc477fd8f768fd922b42536a776a60b1608aa9e6f1f7e3c42b74
font_01_sfnt_off00010381.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10381 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B93 16540 bytes
SHA-256: 5a961bb2cd5654fc33b3bc5a576616209fd3a3084417b1945f235ab02269fbb0