Malicious PDF — malware analysis report

Static analysis result for SHA-256 3da43498edacb9a4…

MALICIOUS

PDF

78.6 KB Created: 2021-09-08 04:11:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 968d870fd0157d9c5aa31fed9ee76061 SHA-1: 2a6a64a7d2188d6dae04abbc44ddb40e79abf8a4 SHA-256: 3da43498edacb9a41cdefd483d03830f591f64084b98fc84d7a856b3a5094493
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file exhibits characteristics of a link farm, directing users to multiple compromised websites hosting other PDF files. The ML classifier strongly indicates maliciousness, and the presence of external URIs and link farms on potentially compromised CMS uploads suggests an attempt to distribute further malicious content. No scripts were extracted, but the overall structure points to a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/cb5dbc18dc721cde6358dcf30dfc754a/1936164313.pdf In PDF document text
    • https://mangallagn.com/images/file/zevasukadorusevozezir.pdfIn PDF document text
    • https://maxlinder.com/admin/assets/ckfinder/userfiles/files/gowokelegipemirufujaguke.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/letemuzanuwul.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f98bd2a18f---jopisabanewera.pdfIn PDF document text
    • https://krzczonowice.pl/gfx/file/janipupisatadanumip.pdfIn PDF document text
    • http://cobe-ing.it/userfiles/files/pibenekoju.pdfIn PDF document text
    • http://hanifeugur.com/image/files/naporusevuwajizek.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/a34f7484eb3bb6c58336c21cf889150c/19566562047.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1628185504.pdfIn PDF document text
    • https://apinero.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075511e86321---peminumanokebebudorom.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612bf73604ebc---21250413642.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/u8u0jha9gvjqqtuqq7ps0rcugp/31452113079.pdfIn PDF document text
    • https://lawyerupsmart.com/tempimg/file/degojumugejivemurokotig.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/82f68b2865a8bc2721ff3ef16a4578ae/4733348235.pdfIn PDF document text
    • https://service-panev.com/userfiles/gurijawopef.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b746ca0650e---zanoxi.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/c7d45bcb122ae2b4853048a69a85fc81/jidozidatimufem.pdfIn PDF document text
    • http://puginternational.com/ckfinder/userfiles/files/11386330225.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/27109372643.pdfIn PDF document text
    • https://iaido-iaijutsu.ru/userfiles_exc/92739310884.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160856942b54e2---javakofoju.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/ee3tarkeerrl9mficertqftov8/lonipulumuborowo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=objective+advanced+4th+edition+workbook+pdfPDF 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_off0000c857.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC857 19048 bytes
SHA-256: 817374c84c56afd332699a3adb49ac779ce3bba407a5634f41dd7f7634dc3baf
font_01_sfnt_off0000fa5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA5D 11120 bytes
SHA-256: cb0781b96a2ad677df5ac1db455e8284036ea863b60907d078b71b96d28077c2
font_02_sfnt_off00011426.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11426 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1