Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b8f07297e7666c0…

MALICIOUS

PDF

77.6 KB Created: 2021-05-24 20:45:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: cbf0f9216bc244ce44f6c21cf15ce9ed SHA-1: ecde3fbc3d4ce128a9c7d88af13414fa63e5a902 SHA-256: 3b8f07297e7666c0c8ba13230503d3782fec1a4d95d721ce8412275bdf77b941
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to compromised websites, many of which host other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body, though partially garbled, suggests a lure related to health information, aiming to trick users into visiting these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607885bf352ce---9949254257.pdf In PDF document text
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/b652523420f95e1efbd3a8cc8ffd41f0/56872384179.pdfIn PDF document text
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/34be7eb1b9a9bf7394fca37e79f7faf3/nologuxumowizizotiretave.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/pajitulovi.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/50061085748.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606dcf39e2ec6---28562195799.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/e702d57afd421e007f8cbc334b48adf7/sojeduvepumiti.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607c9fe3791fd---vobonodevel.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094d25331b3a---17586847854.pdfIn PDF document text
    • https://airshow-bg.com/file/4422520453.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/7107ca10accddadb69d6ce4cdb1b76db/perigolajugesakulorap.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607f092edea1e---kovokadizigok.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=cuantas+calor%25C3%25ADas+tiene+una+cucharada+de+semillas+de+ch%25C3%25ADaPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d6d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6D1 3088 bytes
SHA-256: f5a6010e5f9fc00a912fa25add5ccb25ebe8c4245224df969a22ae60d01903bb
font_01_sfnt_off0000e1d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D7 5140 bytes
SHA-256: 7cae788781e14b29cc5bbb1951c72e24299870f2550fb8562b7b5e66d1d85b9b
font_02_sfnt_off0000f326.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF326 11336 bytes
SHA-256: 491b8e44e735b47d51d3efd550b679b5a1a68b66567ff16cdfc5cce34fc627c6
font_03_sfnt_off000117ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117ED 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176