Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f56920e9bde575e…

MALICIOUS

PDF

77.8 KB Created: 2021-05-28 11:34:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 1e36f77860265fb5cf5f464366d35d51 SHA-1: 1be36c6c14cf410cb07758f899fa5427fbdec504 SHA-256: 3f56920e9bde575e8d2c91f0ddf5a35aaa31064c273c6eb281c77a9789d01031
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple links on disposable hosting and compromised CMS upload storage further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://philabc.ru/uplcv?utm_term=line+graph+worksheet+grade+7 PDF link annotation
    • https://butterfly-propertymanagement.com/userfiles/file/7736159509.pdfIn PDF document text
    • http://insidethedigitaltrend.biz/userfiles/file/wezamipulovu.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b06bb54bea2---87824761291.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608355cf2e14a---83472966873.pdfIn PDF document text
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/ikvgmjpd1tg68e5isn7isnm93d/23133791882.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160814a310f6f1---14958447427.pdfIn PDF document text
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/9349160a8dce0fa464a2dfbe8ac90a20/somikopojefugukaw.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16083a081ecd59---82202326674.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c9c064b785---75400407959.pdfIn PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/iru9ngkmstbritvm36tjcb52lc/92027458535.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bffc719724---gufezukagigodu.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/0ebee75809eb1d3960369f1cee652098/28862628986.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/0gre0ve0alq644ig1moc85e6h5/14908908317.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/16082e99926f67---68810564896.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/act0incfjair3oapmffn6a9tqf/26631230196.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_off0000f1f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F1 5368 bytes
SHA-256: f8c087934a28392c10b69229be98ead0e17a810f2618f8f532b48028f58c96c4
font_01_sfnt_off0001044c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1044C 11188 bytes
SHA-256: 5c9ca3c128388fb7dbd075a8de6799f829b871c84cf42617b771dd31a2bfef41