Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9478e35c026c1fb…

MALICIOUS

PDF

77.0 KB Created: 2021-09-02 08:06:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 7fbe7a336e53515364c3f440762a396c SHA-1: c6b27c3bdaa0883aaa8da398973c8997c59df147 SHA-256: b9478e35c026c1fb91ad16fa845d810e0dbcaee66fd0596ab618fd2652174b31
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various websites, many of which are hosted on compromised CMS uploads or disposable domains. The primary purpose appears to be SEO manipulation or directing users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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 http://easthighclassof1962.com/clients/2/24/240b89ecbeded73b1ae3fdc7544f4fd7/File/36128074313.pdf In PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce51677cc5---gipemovapari.pdfIn PDF document text
    • http://kustari.net/userfiles/file/xurusajuve.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070c706bf151---junopaj.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/31da75a266d598e9f08e26ef0e0a6b6d/29701558324.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f821888d61---nunizam.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/4ghdotu8jf135j1e9i1pncb6fl/ninebesariwod.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/f58dd5407eceec826f5032867f4064d1/kobozisugobo.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/46857352640.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/e99pdc4smtgqts9on1kj9rpk62/gumiwavevafekewefiv.pdfIn PDF document text
    • http://fashioneducation.ru/userfiles/file/17850514142.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/milawelonijif.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847ac13e49f---9340408219.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160af94ce16bee---rusugoxisumerajubabatidi.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16075ab7605df4---wuluxelegifageroxa.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160873e51e2b21---roxiwopupopituge.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/161055a1560113---xavuvogujusozobiz.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//xikolibitage.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160789792d4ff4---zimipupetuvu.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/41607962337.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/1607e81cad01e2---vagolutupudaru.pdfIn PDF document text
    • https://grupo-bahia-real-estate.com/ckfinder/userfiles/files/93849896855.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=vision+ias+art+and+culture+notesPDF 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_off0000c557.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC557 18516 bytes
SHA-256: c409a5535327eb82bed4c2e2d885b0b7e34f8298f48a3fa9ed32b56b3263957e
font_01_sfnt_off0000f536.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF536 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D4D 10432 bytes
SHA-256: 2b19c3e8a85e8adfa24475180d12196d20c3158968892c85e685ef159b3d29c3