Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc6364a0dcd6d169…

MALICIOUS

PDF

86.8 KB Created: 2021-06-10 10:28:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: f340b934194db156e27286f15b8a2aab SHA-1: 879fedf170b63a15ae859d142f5e86b263a90b55 SHA-256: cc6364a0dcd6d169d032db723f0d236fd383f60cab5f351537066f15576a41f2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm pointing to compromised websites. The embedded URLs and the document's structure suggest it is designed to redirect users to potentially malicious content, likely for phishing or malware distribution. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://archism.ru/uplcv?utm_term=ielts+speaking+part+2+topics+with+answers PDF link annotation
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606d23c1c4c6a---pavevajuwijov.pdfIn PDF document text
    • http://www.scsi.coop/wp-content/plugins/super-forms/uploads/php/files/adea57952584c995e98079f49c567284/lofemikisetedesufevuxo.pdfIn PDF document text
    • http://accronline.com/userfiles/file/26377437717.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b7eadee7e3c---95910263954.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/8b88d6e86ed45a54b8bc0143f3f7ca60/65329059268.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160781cf556bb3---zizavu.pdfIn PDF document text
    • http://chixue.com/uploadfile/file/20210531065615.pdfIn PDF document text
    • https://thesaddlebank.com/wp-content/plugins/super-forms/uploads/php/files/8tjqchdmsl9jdomoc2qpkusocj/joxomapabizezimul.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074b56a9a5f8---62832121433.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160832b25d60a8---5113469250.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/fkrkb3rqrp2ks1sjf213nicmp4/nejijela.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac03914f0e1---porawodajuzomininaja.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/q67uo8qaeurpa4v0fh8gd8p1r3/nubiwudaxewip.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/pezokamufuranas.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160b60e32116a1---faxonikiruraxagiruve.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000113e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113E2 5420 bytes
SHA-256: 8016e4fac9ae66cebdfc6bfe2c94239ecae1e0051c42ba7977538235b0f28c6b
font_01_sfnt_off00012663.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12663 11112 bytes
SHA-256: 8a23935b2ab73bc92b99db107a85e8dc85e804b147ab050120f85d3d600788fe