Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bcb7a69646ba97f…

MALICIOUS

PDF

87.8 KB Created: 2021-09-07 07:52:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 871d98c4d0ce2d4f679ba1c75ed205a2 SHA-1: 86ec8e1f9a07e3a182d311ca16b605716426bb97 SHA-256: 8bcb7a69646ba97f36e104c8166d7a49d0d1386c3d45423ef1ed0f9cd09fba71
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload is intended. Although no scripts were explicitly extracted, the nature of the URLs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic suggest a common pattern for distributing malware or leading users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://pixomot.ru/uplcv?utm_term=vocabulario+completo+ingles+espa%C3%B1ol+pdf PDF link annotation
    • https://perfecthospital.net/ckfinder/userfiles/files/94190859437.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160abf825e6274---1833461637.pdfIn PDF document text
    • http://gianphoiduyloimodel.com/Images_upload/files/nijitifowuzikinasudore.pdfIn PDF document text
    • http://tryinvest.eu/userfiles/files/30721123511.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/7a61e14c38455ee09185945f968a9443/64640850004.pdfIn PDF document text
    • http://geoman.cz/data/file/buxavixipifager.pdfIn PDF document text
    • https://shopexpert.com/app/webroot/files/userfiles/files/nugimusojefovikozekobuna.pdfIn PDF document text
    • http://pomocnaukowa.net/Upload/file/55328347164.pdfIn PDF document text
    • https://davaocarrental.com/images/file/87501427349.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb9771a5ad---96269644084.pdfIn PDF document text
    • http://sugarfree-gelato.com/upload/file/safimawalusibemazo.pdfIn PDF document text
    • https://wilocom.ro/ckfinder/userfiles/files/nujux.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/kh7k42t3c90dsvlrfov7po4bjq/829271552.pdfIn PDF document text
    • https://leo.tw/upload/ckeditor/files/varaxup.pdfIn PDF document text
    • http://myphamlulanjina.com/upload/files/zawopiguwusowigexazi.pdfIn PDF document text
    • http://debschoen.com/userfiles/file/wenezutazigebudopiled.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/koxategereregajere.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d433c47f389---furunerelanu.pdfIn PDF document text
    • http://urgentcarepb.net/userfiles/file/gavewa.pdfIn PDF document text
    • https://www.agcontraincendios.es/ckfinder/userfiles/files/38184333519.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091f90cccabb---19725239228.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b75668855f0---wulisirozelo.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/a7c5a0b45d8b246e71c7c4d9ae849af4/jaxaloz.pdfIn PDF document text
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/47145902187.pdfIn PDF document text
    • 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_off0000ea3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA3F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010251.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10251 19768 bytes
SHA-256: f41444f956a41c75d94b559bf9f3d081bf04f223a5a9e51d2d139e7132ecc96e
font_02_sfnt_off0001350e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1350E 11376 bytes
SHA-256: bc8d75c4bbaadd82a66bb0ff3c9943461c1a4e71263884d5cba4c046ad233239