Malicious PDF — malware analysis report

Static analysis result for SHA-256 15143b25087b26c8…

MALICIOUS

PDF

87.0 KB Created: 2021-07-20 15:31:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: bdf53c232870ee879ebe40fb04a966d0 SHA-1: 1f1df04e694e218f2ed0025826b5a34d678c6982 SHA-256: 15143b25087b26c8f5e29e73f00b6405bde9a587fbd2ef7410e738c66609b8bc
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content or phish users. ClamAV and ML classifiers strongly indicate maliciousness, with the PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristic specifically highlighting the use of compromised infrastructure for hosting. The primary attack pattern involves directing users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://greenline.bg/userfiles/file/2049283841.pdf In PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cdf7c30003---vewatuvoduvu.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/qqs8l10da33em7ep9ujbdhss82/66700642644.pdfIn PDF document text
    • http://focostrade.com/files/20210702180529.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/65309851932.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1608ca0e50f608---34373821663.pdfIn PDF document text
    • https://sikanderajam.com/Robinson/ckfinder/userfiles/files/32238653191.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160825321de5cd---59850052142.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/i3vtono80e2p8366g1ie8l8hk3/18274819795.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608bbed1f02d4---pekisalijurezudaz.pdfIn PDF document text
    • http://greenreunion.org/clients/f/fd/fd69eab1634eeea6368acebbe5d5cb0d/File/bijulupitelofukel.pdfIn PDF document text
    • http://softtox.com/new/userfiles/file/92208856919.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160979157dcd96---25901071141.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0118f85b01---38742583214.pdfIn PDF document text
    • https://associazionedynamica.it/uploads/file/72373505709.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be3be8b78e8---11011792571.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db6261af545---80195393037.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/cfad02beb56beb374b5c437047f91cc6/norewiwilenop.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160ac06c3d5d5d---1120327342.pdfIn PDF document text
    • http://atek-ent.com/upload/file/wasaf.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608676798e862---widojazudenekib.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/4ivb0vvbvugl6qpui1q4gnj7go/78348845545.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c60c8ba0b81---lamizigamesuj.pdfIn PDF document text
    • http://gyobel.it/public/file/98223614221.pdfIn PDF document text
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/c8c7b1d63d2fe95014c7a0dab0bc8927/dobusolu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=journal+article+apa+reference+examplePDF 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_off0000f0e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E0 17236 bytes
SHA-256: cb6b67668c7ac7c92a18c4c2fba4560f5c9ec169736dd1891683cb23ddca2c57
font_01_sfnt_off00011de5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DE5 10664 bytes
SHA-256: 38d64e0f31e5b3d5f592d5f4496f9aea2fd5d46fa56c7b2f603c61a1a71107b1
font_02_sfnt_off00013654.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13654 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1