Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b5840a49ac1be54…

MALICIOUS

PDF

83.1 KB Created: 2021-06-25 15:35:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 71669f89e8fdb924f3ebb4f1cebf36a8 SHA-1: 23f9db4317514e35da85c47b05e242c3fb4b95f9 SHA-256: 5b5840a49ac1be54c9cf6610b8d2c2926f4a140273e07c223f094c2044a72cf0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier with high confidence. It contains numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The file's structure and embedded URLs indicate it is likely part of a phishing campaign or malware distribution effort.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://crysiq.ru/uplcv?utm_term=need+to+have+synonym PDF link annotation
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/0c75a6b5f40fdbc3a3ff36fc142fa2fd/kosuzitamigemas.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/7k3vuotlub3bua6t1kvo6iqunm/gunuketetoza.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202105060929075967.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a373c8e743b---muzinevomubolopo.pdfIn PDF document text
    • http://dalnoboy.org/data/filestorage/upload/files/55917347842.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/f7374a5f3bf6506cc731bc2189c934bc/81761309945.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/39g1vggbmd4sqd898op2fktfp3/80686166755.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607176bb914a0---7822789595.pdfIn PDF document text
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/a148a07957b20a053619830dfb096c84/22030712979.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160af9a97c77b8---divutamaxuzijawoxorurada.pdfIn PDF document text
    • http://dchs1961.com/clients/871949/File/70854033928.pdfIn PDF document text
    • https://zegabilisim.com/calisma2/files/uploads/tasuguzanijon.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607429f7a37dc---6184385757.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/cf483c0145ac8700fad5b981160abb02/5986205362.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/757bdc1b55e99608fc93bf7941998626/fexunogefoleni.pdfIn PDF document text
    • http://dominoliberec.eu/images/file/files/13021515515.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_off0000e40c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40C 10432 bytes
SHA-256: eeb1e208354d9ab0ee8778ba91937b17f80c15c5babe86997b98ecaf2c13cb2d
font_01_sfnt_off0000fb94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB94 17140 bytes
SHA-256: d38a3bc2293af22ffb53e19697f269b5c0524c27dfc949bd98b31dfadd3a0f4b
font_02_sfnt_off00012805.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12805 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1