Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b33baee55df4701…

MALICIOUS

PDF

94.1 KB Created: 2021-08-16 22:54:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 350b2e08606dec2936b775f95266f51a SHA-1: c75cf8de9385538d8b2d89554bcd7d4e36326fc2 SHA-256: 5b33baee55df4701789bda8bbe7c6bf481064ea91fa07fcf73288c4de3bd3829
156 Risk Score

Malware Insights

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

The sample is identified as a malicious PDF by multiple heuristics and a machine learning classifier. It functions as a link farm, containing numerous URLs pointing to compromised WordPress uploads and other disposable hosting sites. The primary purpose appears to be directing users to potentially malicious content or phishing sites, consistent with a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://shreenathtechnologies.com/userfiles/file/jodugizuduz.pdf In PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/987cfd7e3671117d3c1cb694b1058eab/78005232607.pdfIn PDF document text
    • http://koslita.eu/ckfinder/userfiles/files/92408825922.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/3d88cdd8cbee94bd6d75f5719dc42424/58156433695.pdfIn PDF document text
    • http://interiorconsignments.com/media/file/24815211916.pdfIn PDF document text
    • http://fructusartis.com/i/File/8095499471.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091b98a4dfb6---kolurokedetaveni.pdfIn PDF document text
    • http://taxicityplus.ru/userfiles/file/73998227858.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160782c79eba37---wofibusij.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/files/55319431868.pdfIn PDF document text
    • http://congtyvima.com/images/Download/63745793938.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160717b2003b40---xakiv.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/3ojh02egvbjb757b4h60gt32t0/59653568789.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/2893512ab31842f4affa7cc322cc0b12/xuxerefizes.pdfIn PDF document text
    • http://grandchainfamilyfoundation.com/clients/85333/File/230784424.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/lovuxe.pdfIn PDF document text
    • http://st-johnson.com/Uploadfiles/files/ralugibujug.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/wobodewe.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/32guibjin06hseduqc3nf35ohn/88804550368.pdfIn PDF document text
    • http://www.azurwelcomeservices.com/userfiles/file/90979123397.pdfIn PDF document text
    • https://www.marjojaspers.nl/ckfinder/userfiles/files/65930986116.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/rr5pq8kpml4femnnjvh9lc3v31/gorixopugugadefa.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8af6275f13---dugogekekusaxurag.pdfIn PDF document text
    • https://menu2uplus.com/images/file/91875966686.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=how+to+take+apart+a+sole+ellipticalPDF 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_off00010d4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12564 10432 bytes
SHA-256: 1d298b0e1a163b4e8a75829e318db5c090ea0929b45f480d64dcb2a28dd1cee2
font_02_sfnt_off00013d39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D39 17216 bytes
SHA-256: fbfaea5903197e84562a2a19cccd547c3fd66ad8dfc531998e6a10c074e2589c