Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cf6cd3f5e8479a0…

MALICIOUS

PDF

82.7 KB Created: 2021-08-20 17:32:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 9b2a9edb6db50b0de4ac9aba80ef3b9b SHA-1: f0ba52f0d87e6ab5e328821234552a690e70344a SHA-256: 8cf6cd3f5e8479a022825808064a50e47ea11a3db50d178a93be2fcff5ba1e98
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://actorconseil.com/files/file/1324077940.pdf In PDF document text
    • http://imosa.asia/uploads//files/202108091035016629.pdfIn PDF document text
    • https://egyiksem.hu/uploads/file/mofuviz.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d8b613e311f---zibav.pdfIn PDF document text
    • http://bwc.lt/i/92892473604.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/gqouf4r64ulr5vnkev3k1gmgc6/58764907239.pdfIn PDF document text
    • http://merwepizza.com/upload/file/mabavusajobijibovi.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160bbfa914f1ba---fegekewiragifeteb.pdfIn PDF document text
    • https://www.ideaklinikbursa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f9323421b4---vepufirexesolelorik.pdfIn PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/46128236088.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160adbde683159---22585682344.pdfIn PDF document text
    • http://www.dagmarsvendova.cz/admin/js/ckfinder/userfiles/files/gefog.pdfIn PDF document text
    • http://www.bufolari.com/public/immagini/file/rufojemupabupive.pdfIn PDF document text
    • https://shopinhome.com/ci/userfiles/files/jutikazatageton.pdfIn PDF document text
    • http://csc-020.com/userfiles/file/20210810100654_5sxz82.pdfIn PDF document text
    • http://teraval.cz/res/file/38244907624.pdfIn PDF document text
    • http://nattuvaartha.com/assets/ckfinder/core/connector/php/uploads/files/69900660103.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/bf9ec9c6dfd5fa907cd96631f9ac487b/jixinuvabix.pdfIn PDF document text
    • https://p87.hu/files/20795737676.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16086f06047ac3---fitikilisadapesow.pdfIn PDF document text
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/22359189013.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/549a6bbefe1d84131b27121c95a220fb/fusuji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=how+to+make+a+monthly+budget+template+in+excelPDF 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_off0000de96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE96 17016 bytes
SHA-256: 709751d0304ae234a3d674ca0041cae56abb0763eab9e926a1a647a6a7483804
font_01_sfnt_off00010ae3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE3 11320 bytes
SHA-256: 0b45cbdfd885167eee0bfdd76cc129825933c5c4cfa9c43f886e1b3f4d891a20
font_02_sfnt_off000124e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1