Malicious PDF — malware analysis report

Static analysis result for SHA-256 1137d709aaae6827…

MALICIOUS

PDF

89.2 KB Created: 2021-07-03 13:54:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 7dd15f8c1bfd5f34ca9a1d1b83ed6512 SHA-1: fe995432e7cf74ed61619c2d888c231e068ce1a5 SHA-256: 1137d709aaae68273de7a535b09d5f3758b6efc6c0959f346d6cf15d50f03d00
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier, exhibiting characteristics of a link farm hosted on compromised WordPress sites. The embedded JavaScript stream suggests an attempt to execute malicious code, likely to redirect the user to one of the numerous external URLs found within the document. These URLs are designed to appear as legitimate file downloads but are likely part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1609f23fb88cac---975299485.pdf In PDF document text
    • http://kielcenoca.pl/files/file/seziruxodimevusezabawi.pdfIn PDF document text
    • http://thallo-food.hu/uploads/ckfinder/userfiles/files/xiturokuloleniro.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/bapexovexijinepitu.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096190faae9d---dopex.pdfIn PDF document text
    • https://ecotranslation.ca/upload/editor/file/dutajanujuvizibu.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8e8283c513---96890049332.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/m47ntp64aodfini1v7e7dh289c/1056409190.pdfIn PDF document text
    • http://seamacros.com/upload/file/96767145823.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/16ntj8c7r27nbrn8n5hu3f2jr3/56239806828.pdfIn PDF document text
    • http://www.dramayaramendes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607dbbbd94faf---dixeki.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/71342127240.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/2327483524.pdfIn PDF document text
    • http://thicongdiennuocmiennam.com/uploads/files/42631707654.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606f25cc05804---dovorulameruxeg.pdfIn PDF document text
    • http://telmeed.com/web/ckfinder/userfiles/files/56874989699.pdfIn PDF document text
    • http://christopherdallo.com/file/66716278880.pdfIn PDF document text
    • http://yourhealthyanswer.com/ckfinder/userfiles/files/68001537897.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/0f0d71c65adf2fdb14404f34636874ef/17130962108.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/xatepufifamegowidide.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/6ldmbranh26s2udcvuee609525/83019051613.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16076c57b562bc---39530734709.pdfIn PDF document text
    • http://df-foundry.net/d/files/2475467775.pdfIn PDF document text
    • http://arserwood.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210509001418502064922ggn.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=picasso+all+paintingsPDF 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_off0000fab8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAB8 10316 bytes
SHA-256: acd789702b8d45505ef46816d07122d23b26cacd98cbc2880f4c9fffb3edd3be
font_01_sfnt_off0001121c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1121C 17604 bytes
SHA-256: b833e2a1612879cb23bb59734dd5f2d5712c9b0834029e66b04e4db887207add
font_02_sfnt_off00013f74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F74 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1