Malicious PDF — malware analysis report

Static analysis result for SHA-256 a406d92f158cb4f5…

MALICIOUS

PDF

81.9 KB Created: 2021-09-01 21:25:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 535ea23d66b48be90d630be93712ccef SHA-1: 3b049cabbd949fb8ee86d275b85f731b33826c68 SHA-256: a406d92f158cb4f587923a524fc04e65c15ad2f43314f43139d7f595f06261a1
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Several heuristics point to the document being a link farm, with many URLs hosted on compromised CMS uploads and disposable hosting. These links are likely intended to direct users to download malicious content or visit phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a89ac941498---supimezudirusano.pdf In PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/3d6hallgr6bu5mqbqi734slj26/gonurigerumiwisegonufi.pdfIn PDF document text
    • http://yearbookplus.com/uploads/ckfinder/files/31221539909.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/76231109944.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/70254519614.pdfIn PDF document text
    • https://frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/fivejixawivod.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160928eb585ec4---mozolajuzidapajexowasu.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/16606914767.pdfIn PDF document text
    • http://fogathajtohirek.hu/fckfiles/file/31842084693.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1609fe15eb9d30---bedamuxe.pdfIn PDF document text
    • http://oguzlarotomatiksanziman.com/depo/sayfaresim/file/tetefapibakoxubezu.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607739732b424---57036595354.pdfIn PDF document text
    • http://ucity68.com/clients/e/ea/ea220da86df44fb0ae3b7c8e8295ccc1/File/22243348774.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/5ca25cde39e8840706f6c08f6fe4754c/35228968210.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/fc8eda811ab4660b05152bbd38d61d5d/fexotisagolizes.pdfIn PDF document text
    • http://automozg.by/upload/editor/files/75577000197.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160846c20bc49b---74524649324.pdfIn PDF document text
    • http://beautybybelief.com/admin/images/file/12647673380.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/dd8ae26ac66b017a966ccada39088d7c/67562995874.pdfIn PDF document text
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/fe1ca5c5f86ed1eaf42add8ff73e7569/1270248986.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/85077920978.pdfIn PDF document text
    • http://nbmounts.com/userfiles/file/1630308492.pdfIn PDF document text
    • http://mea-travel.pl/userfiles/file/jawozagukalurawifir.pdfIn PDF document text
    • https://www.sudoku-cool.com/ckfinder/userfiles/files/69309616355.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/76dc1b01b2fde68e0b2df0d2c44af57f/64562154354.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160965ec9d4ebe---pikataleses.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=download+unity+assets+bundle+extractorPDF 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_off0000d6d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6D3 18136 bytes
SHA-256: b7627534d3a6a786d5114c6e43dab18f5d5585100f2fce268f269f4fee040bf8
font_01_sfnt_off000105ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105ED 10904 bytes
SHA-256: aa52104a798cdd2f40696d587b45321851f2b0ac20c4c80da3dd7fc8e7ee4b30
font_02_sfnt_off00011f6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F6B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1