Malicious PDF — malware analysis report

Static analysis result for SHA-256 50082403a9f6a2a5…

MALICIOUS

PDF

81.2 KB Created: 2021-09-07 21:20:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ddd8031e7bbc7abd2892be01bef8efcf SHA-1: d15be4f8bbb2feaf76cdfa465026de65015506e3 SHA-256: 50082403a9f6a2a523f68b4653202d0f768e74f869fb401dc070d54c6f4054b6
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous domains, many of which are hosted on compromised WordPress sites or disposable domains, as indicated by the PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure itself is designed to lure users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://w-f-l.de/user_img/file/jugulonokaf.pdf In PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c6c4c19f5aa---wokusudapol.pdfIn PDF document text
    • http://kargo-box.com/uploads/files/liputuzevomidunez.pdfIn PDF document text
    • https://grafconsulting.pl/Upload/file/jugufobotosakirikemepofi.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076296eb7452---39073730296.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f6e8daf0666---jemezuwuxobam.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/moponalurepalazewabuw.pdfIn PDF document text
    • https://przygodanaukrainie.pl/admin/ckfinder/userfiles/files/13915002480.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/9764ud7k2l25geca8q2r3a2ce1/52678692586.pdfIn PDF document text
    • http://amtutoring.com/clients/865321/File/kumovubutanaxemoso.pdfIn PDF document text
    • http://csc-0898.com/userfiles/file/20210801171508_sf2ie3.pdfIn PDF document text
    • http://biirbeh.mn/images/content/file/13356841035.pdfIn PDF document text
    • https://villanakarin.com/userfiles/files/74374859202.pdfIn PDF document text
    • http://fairbank-ia.org/admin/ckfinder/userfiles/files/30692081801.pdfIn PDF document text
    • http://belovosushi.ru/files/botikub.pdfIn PDF document text
    • http://valifyrepapillon.com/clients/6/68/68e1c6a84db99a04c21676ff826d6e37/File/xogozoroniwinasesuko.pdfIn PDF document text
    • http://bydnjl.com/userfiles/files/58081279077.pdfIn PDF document text
    • https://flexi-cms.com/uploads/file/dafibugotitilev.pdfIn PDF document text
    • http://heorungminhphat.com/luutru/files/37552638328.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/70b041657f510fe2effcdc7c2dd6a78e/5668369404.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/a99e92f7babcc4f6c99ed30c837e2dad/65914974384.pdfIn PDF document text
    • https://alsharqcc.com/userfiles/files/91092461667.pdfIn PDF document text
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/80da2e00ec265188a008ec6dde24a81d/1682301437.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084430ea32e0---napipodetugujemal.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/53839725324.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=adenoma+hipofisiario+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_off0000d3e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E4 10600 bytes
SHA-256: 331ca5b3a9bab2ddbdb11a1fbbb65f9b5c98c3f6fc1b1dedce99c59cd493fbd9
font_01_sfnt_off0000ebdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBDB 19204 bytes
SHA-256: 6ed6210204b3c1d2077d1a4ecedccf9b84e8822d152bbee0c35c47d829eb0794
font_02_sfnt_off00011dd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DD2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1