Malicious PDF — malware analysis report

Static analysis result for SHA-256 406f1f16e9daf858…

MALICIOUS

PDF

72.0 KB Created: 2021-09-19 15:50:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 51b9d714dfe9a8677991334c41d59e15 SHA-1: 2d7d428182e0303e785097e73876c4aabe97c70f SHA-256: 406f1f16e9daf858a00eed8e60d2dd54d298a01ea1bb9afc2480eb155bedde65
96 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicative of a link farm. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on disposable hosting and pointing to compromised CMS uploads. The primary purpose appears to be directing users to potentially malicious or SEO-manipulated external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://pixomot.ru/uplcv?utm_term=android+and+ios+compatible+games PDF link annotation
    • http://fioredda.com/userfiles/files/52972874178.pdfIn PDF document text
    • http://www.prakashirrigation.com/uploads/fck/files/dotima.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/4f605c399da1488e94da4823a84216f5/kikebanajujijidupawe.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/t0k3vgi8gu69ckdpo9hltd37ev/liwozakoritipologes.pdfIn PDF document text
    • https://biomisszio.hu/tmp/40987188797.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/kabogur.pdfIn PDF document text
    • https://flammerouge.ch/userfiles/files/18796564831.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/26802840788.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/lvf5pt7eu1favhe4je36vpaneg/75877571167.pdfIn PDF document text
    • https://asoriofrio.org/ckfinder/userfiles/files/nijijepelerekowofefanaw.pdfIn PDF document text
    • http://casinodanmarkjackpot.dk/userfiles/file/62390349658.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/cab7b691305805ee918ff4fa221c57b8/vipakevakepajikiwitogim.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/orh4r5qd7albnujaikfjf7did6/suleneguzar.pdfIn PDF document text
    • https://kamwalibais.com/userfiles/file/62423014230.pdfIn PDF document text
    • https://www.champagne-auge-dascier.com/ckfinder/userfiles/files/jesapakidif.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16136a8b35c0b1---mevobop.pdfIn PDF document text
    • http://safiorida.nl/operatori/userfiles/file/tekedug.pdfIn PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/zojili.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145dd58c164e---48326090776.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/14817196268.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/98959239092.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4d8351bee---85080831252.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_off0000b6b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6B5 10980 bytes
SHA-256: 16d12356dd4e20883bdf4d7dcb7be220f1911509f2691c7df88ebff9127f4452
font_01_sfnt_off0000cfc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFC6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e7d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D8 16564 bytes
SHA-256: 7e392e0dbd93fb585d98e70b6497916d9d5fe19cb8f2ef2cb5027d95a45f9cb4