Malicious PDF — malware analysis report

Static analysis result for SHA-256 a41f1bfd5c3d33c6…

MALICIOUS

PDF

83.7 KB Created: 2021-06-29 13:49:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ed68350bafe1c4940891bc14484184fb SHA-1: dee99186cde7fd9ab60b23aca4bef4979d36cac1 SHA-256: a41f1bfd5c3d33c6b6ec7a8c42b714faae3767ec8c83ba8e0346ae4df944fa8d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics points to the document's primary function being to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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=work+reference+letter
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/c50fd1141e976fec566258137755d207/faluxedevetubinazamexoj.pdf
    • http://limuzine.md/userfiles/file/86344185620.pdf
    • http://spoilersmensgolfclub.com/clients/865201/File/dumawasafuzuzo.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090adb5350d7---funug.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609df7b7d6b1e---18858600663.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077156961b9b---lavotinufibikatowes.pdf
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160808d2fc03fd---wagutotukilu.pdf
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/4a69f2624948dcf3260f26e298c73cca/55750065503.pdf
    • http://www.colormotion.cz/UserFiles/file/nigezota.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d52703dc66---xokapavilulivago.pdf
    • https://autotrans911.com/thread/admin/uploads/file/wenisavero.pdf
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/dc2fe64ad9c5e59a9286f7034dd3ac57/beganidafibinugitexofobix.pdf
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e2007c31f---koxefujodegumukupegob.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160870ab34e3bf---vomigisowuxuvoriremewujer.pdf
    • https://aprilboya.com/userfiles/file/jineboruteresepomepid.pdf
    • http://laulumaja.fi/ckfinder/userfiles/files/bupaxoxigomidaxajileno.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/aoj6nl7o8asava3fm3geh0pqf2/zofuvonorafizifemad.pdf
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076e4d64dcfa---77637356975.pdf
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160718dbb1a80b---64936650426.pdf
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/t2voo96n84cblssnua1cjvqf5t/35918096925.pdf
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4405c95149---11216139820.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/e7af4c4ee7f1a0a2c6d17c0b6852cb3e/pumupulalivotivi.pdf
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/358b0b18a83c565a29f5eee7b2fafd72/37535906128.pdf
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/f7d8e910d3b37ceaf7d9842d34c0793f/zaxewaregepokijavodejew.pdf
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/bj0hr6f1m0p7cu3cdo7s05vh22/29691520162.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e832.bin
cc2965af149c28a31e281e9284980426b2abede5d80f5c6fb611887a57620da1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE832 9992 bytes
font_01_sfnt_off0000fe7c.bin
248c7df1dca1f936d146d55ccb9e6b2e45347f183a9921d076d0652acae54d7f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE7C 16176 bytes
font_02_sfnt_off00012810.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12810 16792 bytes