Malicious PDF — malware analysis report

Static analysis result for SHA-256 66b4e1bbf4fdd8ac…

MALICIOUS

PDF

89.8 KB Created: 2021-09-05 11:42:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: 5d6d18d334b0a97fc00882cf2ee05e53 SHA-1: 008ab1e9953767d6eca7d9e2ef1e0bec4277cb0f SHA-256: 66b4e1bbf4fdd8ac1d7c41f4d0aed89263c16abc7c7b4c6b8a108362303ffb12
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609115eac48c6---vidofebenisulewemu.pdf In PDF document text
    • http://seoulmenu.com/uploads/files/57194980976.pdfIn PDF document text
    • http://frickcontrols.com/uploads/files/vowemejidijipakaw.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160bdb0430a564---60131240822.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/30gtq6mste3ff310v4o0bt7p84/veluvuboxerow.pdfIn PDF document text
    • http://propellerclubsandiego.org/uploads/files/60527975379.pdfIn PDF document text
    • http://sgrappresentanze.eu/userfiles/files/80136487822.pdfIn PDF document text
    • https://lacecinella.com/writable/public/userfiles/file/94427743442.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/57289811440.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/58v7j0fj5qdbjriue9m2d4sars/mosaragivezi.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/fab5d98f1274ca156652514b2f5b3d23/ruxiboxamowajimerelesogot.pdfIn PDF document text
    • http://boletos.luzservicos.com/ckfinder/userfiles/files/36912277739.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609abf367bba3---lukafu.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/gelazimimiwutomi.pdfIn PDF document text
    • https://www.ewdel.cz/ckfinder/userfiles/files/27600802699.pdfIn PDF document text
    • https://valubil.com/public/uploads/cms_file/cms_files/292189915.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/pg1b02var2pv78d1u4p2fgrv17/madotenutob.pdfIn PDF document text
    • http://www.chubsorn.com/file/files/zatefotiman.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f40e8d1842---dexipoterurifejesurekaluw.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/fej7vrm8uit1876llilshn4l88/mepimav.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c17583308d---72895945178.pdfIn PDF document text
    • http://mjacz.cz/soubory/files/81196172528.pdfIn PDF document text
    • http://asfalon.com/__files/file/74916763043.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/52731855e08e405c92698a8f8d048200/7967265570.pdfIn PDF document text
    • http://maremio.ru/admin/ckfinder/userfiles/files/dizarudofugutavi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=1995+pontiac+grand+am+repair+manualPDF 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_off0000f71d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF71D 11044 bytes
SHA-256: 8386e442ea1574f208b73c9d8462c19c2f5335c6475d39070a8e66f966abdc64
font_01_sfnt_off000110a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A9 19012 bytes
SHA-256: 8defea9f14539d89457f4a49267f3d3ea5d2b7cd53d5e0f81402253d235475ca
font_02_sfnt_off0001415c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1415C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1