Malicious PDF — malware analysis report

Static analysis result for SHA-256 35f5c21f22d0ca52…

MALICIOUS

PDF

227.9 KB Created: 2021-06-27 11:46:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: cbd1885cc73b2f2c1ca939da8f429ff2 SHA-1: dcfb73bbc939b00d57b865ede60ae8fde90c591a SHA-256: 35f5c21f22d0ca528fe35427ea51670f6b52a242863ca2460818a87d1d54a544
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm designed for phishing, specifically leveraging compromised WordPress uploads. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and associated URLs point towards a phishing lure that likely leads to the download of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9800

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
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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.
  • 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.adilaltinsoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070828909584---87426513832.pdf In PDF document text
    • http://gelateriacool.it/userfiles/files/falujatilojuxunoxofaxujuw.pdfIn PDF document text
    • https://chaplains-camps.org/upload_picture/file/xonina.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/mijesodusudop.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acca9ea9be9---jumosupekupodukagufut.pdfIn PDF document text
    • https://auto-rujo.com/images-editor/file/telovi.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/givubolotubosuzejigez.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/c430091c78be520132f60f918757fa57/81307874090.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/064f4f25bd292cce7bc45699ce2ba2f3/koxubigibozojujujupobupa.pdfIn PDF document text
    • https://sjalikave.hu/pictures/file/65717550220.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609eec284e814---zazar.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/6b68e56e97156ea38ffcd0886ab93a85/42121624457.pdfIn PDF document text
    • https://codecs.ro/images/file/rozibax.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/ropelezudoderumugul.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6eb0edda15---54139007926.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/ubi27dbkvebsg378h8hmhrppeq/10166026174.pdfIn PDF document text
    • https://landbondcorten.com/attachment/file/989b9aea10956997bf97e233bd30f4f8.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/k2bi424d9icqc0r2lns54ldmdl/tipokulomet.pdfIn PDF document text
    • http://alliance-ltd.com/userfiles/janotasuralu.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/46ebq66un9gj0ofn8i87ec9ke4/4931333849.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/d75b691f81cdb61bfad90b0df5cca910/novajimiza.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160943c1fce783---26648664840.pdfIn PDF document text
    • http://magooferta.pl/uploads/fck/file/38038757939.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609236e5b1327---78464835298.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=the+witchet+1PDF 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_off00031651.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x31651 9728 bytes
SHA-256: b009c8fca80e58bb0c528a65f31784342c8e51f205498a6cadd389285f76d984
font_01_sfnt_off00032bcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x32BCB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000343dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x343DD 31876 bytes
SHA-256: 3274a4735b628c62d58635bc14c3969b3ff6c7161fa3a16ea4ae4fe7b89d066f