Malicious PDF — malware analysis report

Static analysis result for SHA-256 73539749ecb17f0e…

MALICIOUS

PDF

105.9 KB Created: 2021-09-09 15:50:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: ff88e179b63f77de80855212f4dd6f69 SHA-1: b56c263b2a9ddd6ca40121e0bdeb79c7a29c6b00 SHA-256: 73539749ecb17f0e6ebcd52fb8fd2013e6341db110e7e584a0784c3436a8df50
156 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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://manage3.realtourvision.com/rtv/ckfinder/userfiles/images/files/bilibodoxipive.pdf In PDF document text
    • http://theclubburger.com/uploads/files/gimukawuleta.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1612f144b09d91---55337273910.pdfIn PDF document text
    • http://vanguardhungary.hu/userfiles/file/sogemaxebupoxotitavedugi.pdfIn PDF document text
    • http://oilmachineydy.com/d/files/gelukujujuv.pdfIn PDF document text
    • https://kompaspt2.com/contents/files/92797599755.pdfIn PDF document text
    • http://ccspatti.org/userfiles/file/43364166429.pdfIn PDF document text
    • http://novo-foto.ru/ckfinder/userfiles/files/92906366960.pdfIn PDF document text
    • http://xn--9i1b14lzokxjcrti5um.com/upload/fckeditor/file/vetejadub.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613852ad32d31---tufosofanivalodir.pdfIn PDF document text
    • http://margheritango.it/userfiles/file/kadumunulanuxid.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139312772637---374857200.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/98510561364.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/cd633a197889768d6a4618d2e3ef9cdd/leguto.pdfIn PDF document text
    • https://angel-juicer.com/FileData/ckfinder/files/20210906_0DCBE41B883A23CB.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/28339039521.pdfIn PDF document text
    • https://lnpro.in/ckfinder/userfiles/files/62502456783.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/64a8d7267c90ea534961fe8a061367fa/raxugokeduwuguxe.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613459cc6b280---39964949058.pdfIn PDF document text
    • https://longislandinvestmentadvisors.com/nini/userfiles/file/webarulomepigunafikam.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/161357ccf2febc---vezesosuke.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=bedtime+stories+in+tamil+fairy+tales+pdfPDF 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_off00013065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13065 10824 bytes
SHA-256: 6434b7c1269ab0846b7176fed748b8aa49413db05a8367b0dc8c30201211772b
font_01_sfnt_off00014962.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14962 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016174.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16174 21504 bytes
SHA-256: b658cc668ffdb9dd0664a06ca64e793a0d45228fba0e8df69d8a0c1844240b25