Malicious PDF — malware analysis report

Static analysis result for SHA-256 4094406c8d36cfd6…

MALICIOUS

PDF

82.2 KB Created: 2021-09-07 10:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ddfa1ca211b36566fc0e79406e71b01f SHA-1: 64b7bec866e31784290ba11f0e5839aa7f227ca3 SHA-256: 4094406c8d36cfd6eeff59accead39bf24798bc15250dbc02f14927c827340d3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or to redirect users to further malicious content. The primary function appears to be acting as a link farm to distribute traffic to various potentially harmful destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://oniceh.ru/uplcv?utm_term=olga+tokarczuk+ksi%C4%85%C5%BCki+pdf PDF link annotation
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a19b3130857---ditele.pdfIn PDF document text
    • https://almentispharma.com/ckfinder/userfiles/files/43496397017.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/gipozodexejusozituram.pdfIn PDF document text
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/29928b14403f52d522f68869d8cacdef/fugopulugit.pdfIn PDF document text
    • http://aquatherm-graz.at/files/wixube.pdfIn PDF document text
    • http://xn--or3bi2da319p.com/upload/fckeditor/file/18178316278.pdfIn PDF document text
    • https://digireg.es/upload/46604942240.pdfIn PDF document text
    • http://rogo-rotterdam.nl/files/xevarare.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/pazoxit.pdfIn PDF document text
    • http://kondicionery-dzerzhinskij.ru/upload_picture/file/lezatawiditoret.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/0hij3hr94461vakru45bihn3r2/zepetusop.pdfIn PDF document text
    • https://bor-diing.com/upload/files/nevisazolog.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/28814815707.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/90255875696.pdfIn PDF document text
    • https://bahispesinde.com/gnc/veri/_files/judiz.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608a024f6c5bf---87604953251.pdfIn PDF document text
    • https://bnbtravels.com/ckfinder/userfiles/files/74903543379.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160944cf140698---bufuxepun.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/3aad5bde6e08c562e9a83c6b44c83006/sumigubisonobes.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160a0ab6f9f9e9---90290401025.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-5-5/20210505105859780164.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_off0000d916.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD916 18984 bytes
SHA-256: 98de2a8b1db82a753cfec5f3475cebdc4528b8263a2f9cdec6f0c572e9f45460
font_01_sfnt_off000107c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C1 11180 bytes
SHA-256: b620c9d8f2806125407ddbaa3b6fb980e27743ff4cf749718d5b30ed6f91647a
font_02_sfnt_off0001217b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1217B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1