Malicious PDF — malware analysis report

Static analysis result for SHA-256 d59c96556b12cb40…

MALICIOUS

PDF

85.8 KB Created: 2021-08-16 10:43:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 904f4bdebfcc3b6d7ef1d05c84e51371 SHA-1: 41a81b6dd17c473ab12de61961bf304b7941282a SHA-256: d59c96556b12cb40cc65522af13bed558d06126f6bc1f28b35f3efb9fe011057
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs that point to compromised websites, many of which are WordPress installations. The ClamAV detection and ML classifier strongly indicate maliciousness, classifying it as a phishing trojan. The sample's structure suggests it's designed to lure users into clicking links that lead to potentially malicious content or further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/c4904626413fea604a73ee06450d3048/50615185720.pdf In PDF document text
    • http://kimwendelldesign.com/ckfinder/userfiles/files/5841550722.pdfIn PDF document text
    • https://ehlibeytalimleri.com/resimler/files/vatoxenufapozomaxasefip.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/16109484717024---8926183565.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb82b67336---lukob.pdfIn PDF document text
    • https://mintedimages.com/ckfinder/userfiles/files/vosodomoxuka.pdfIn PDF document text
    • https://vroa.pl/chplusfiles/file/84786716485.pdfIn PDF document text
    • http://hyundai-dongdo.vn/images/files/sakavonu.pdfIn PDF document text
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/24332463727.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/lafewuzup.pdfIn PDF document text
    • http://blesk-stroy.ru/userfiles/files/74470778721.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16108bd31b9c28---siwuresodukijomuge.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/befigijog.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/pinunerobufolinawimapipok.pdfIn PDF document text
    • https://www.lashharmony.co.uk/wp-content/plugins/super-forms/uploads/php/files/7bsfg6dh8rnb08igk7q98h1cfh/sojururizoso.pdfIn PDF document text
    • https://kimcert.net/E/file/96921782343.pdfIn PDF document text
    • http://maciejabramowicz.pl/upload/files/file/95614342385.pdfIn PDF document text
    • https://abouelhoulgroup.com/userfiles/files/somupumab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=happy+birthday+dear+friend+male+imagesPDF 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_off0000eb15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB15 11068 bytes
SHA-256: eadbf85c497c7a26386fdff2f7f2cd7091e7499a9a9017bdf4752f757a43c44d
font_01_sfnt_off00010433.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10433 16796 bytes
SHA-256: 049f5703e25cd0dd281c1701a4ed32420f896ae139cbc58cfe1d75d9939a0958
font_02_sfnt_off00012f98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F98 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1