Malicious PDF — malware analysis report

Static analysis result for SHA-256 db787c4a017a14e5…

MALICIOUS

PDF

96.7 KB Created: 2021-08-01 05:17:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: dc04ac8c06c91a0f9acdcc35ccaa6408 SHA-1: a4fd7075c96993725be60a3524a68a8f45fa783f SHA-256: db787c4a017a14e582efe4c9c286724efec107affb5bc7a47959c8a6c4b624bc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9889

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://krisoc.ru/uplcv?utm_term=medical+fitness+certificate+format+pdf PDF link annotation
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161024f18ed425---65306024847.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/gimadovoxivitixegokat.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/s3p5rkjfuqnv9tao8krs70epoo/56842043219.pdfIn PDF document text
    • http://beerskiboot.de/img/upload/file/wibukojazarepaluva.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/80397828732.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a08830cbd3a---78788664436.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16099bc13be78f---74330551231.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/88195175638.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/54401855957.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/b72725ba9e04b229be8c5471414b9129/63101787909.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b29d4688d35---bapewimubupuwuv.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/bdd56ff32c425396e9f37edaee5970fd/xomisemedupaxutev.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c94502f096c---18530222977.pdfIn PDF document text
    • http://quangcaosms.org/media/ftp/file/zajokanolapise.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/63f0f72cde41b8ab15f3fa6a276710e4/sawusigare.pdfIn PDF document text
    • http://bukharaalpharetta.com/sites/default/files/file/85559460945.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/dapadu.pdfIn PDF document text
    • http://kxnjl.com/userfiles/files/vedowesewagupukejiliwetur.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5b6d81c07---85105528329.pdfIn PDF document text
    • http://candientuvibra.com/images/file/33125553054.pdfIn PDF document text
    • http://ccspatti.org/userfiles/file/xakazi.pdfIn PDF document text
    • https://vkgnassociates.com/dayafter/uploadimages/newsimages/file/tosuxo.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9fc0903d1---fobotorejemadodiv.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/pibulepazefo.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/rejopidinufegatoxogovir.pdfIn PDF document text
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/48ccd0e65fc34f3309a82da603b18a2a/pokazamawajoj.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160785c38be524---zononopafunizet.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_off00011562.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11562 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012d79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D79 10772 bytes
SHA-256: 91289b6ec336f020ef615d5171de23d8889a7f2613c9178cd6b4c93c1bfd9d9f
font_02_sfnt_off0001462f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1462F 17192 bytes
SHA-256: 2868e0c7c782833aef7ffdf36cba778b44628bffecb183cc946c5e2abe9dbccd