Malicious PDF — malware analysis report

Static analysis result for SHA-256 e881ccfc8944906e…

MALICIOUS

PDF

80.1 KB Created: 2021-09-18 09:28:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7bcf31bb68e6eb8f8204967a67bdcb99 SHA-1: 9983c70f74e4f964109f8ac7e99b275636fd9aa3 SHA-256: e881ccfc8944906ec145dd7bc05b08a308e115a30b6a1bc74db6c6dd25ed6af1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, indicative of a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://queure.ru/uplcv?utm_term=pmi+plus+minus+interesting PDF link annotation
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/k2m5baphpvv0g3cgg2glkcj4vd/dezinelomigitapasifetuv.pdfIn PDF document text
    • http://csc0512.com/userfiles/file/20210913013435_zrvyfy.pdfIn PDF document text
    • http://ottuk-e.org/userData/board/file/33591722498.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210905161756787.pdfIn PDF document text
    • http://sanalights.com/admin/admin/uploadfiles/file/84404566565.pdfIn PDF document text
    • http://datcat.vn/2018/file/winixukudozanuwutilalaku.pdfIn PDF document text
    • https://kuraniterbiye.com/resimler/files/lezepe.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/h28dogg6rje4m2vii5mq6jvue3/24982795976.pdfIn PDF document text
    • http://margheritango.it/userfiles/file/79194868214.pdfIn PDF document text
    • http://way-of-spirit.ru/upload/file/50142556379.pdfIn PDF document text
    • http://starcity-vinhomes.vn/app/webroot/img/files/39197398312.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd7aa545c4---43283470576.pdfIn PDF document text
    • https://stl-log.com/htdocs/cljr/data/files/42250529128.pdfIn PDF document text
    • http://prabashproperties.com/ckfinder/userfiles/files/sojak.pdfIn PDF document text
    • http://mojahotels.com/ckfinder/userfiles/files/28311298291.pdfIn PDF document text
    • https://ptogel2.com/contents/files/rufusuxisotaseroxi.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613d7820232b8---boxoximetilu.pdfIn PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/7803838072.pdfIn PDF document text
    • https://grnca.org/img/files/files/sewoza.pdfIn PDF document text
    • http://thietbiytedaibao.com/media/files/jerewu.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/45926391434.pdfIn PDF document text
    • http://decom.pro/admin/ckfinder/userfiles/files/bugedetifebukesenote.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_off0000d601.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD601 10416 bytes
SHA-256: 76650bae93c8894ce60534cf83a09a0b8a2274ab616a3840d31e199b1483d097
font_01_sfnt_off0000ed87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED87 17788 bytes
SHA-256: 978075616051d2bf343900775f53043e0bb142e223e7c1f795667d3cd20725d6
font_02_sfnt_off00011b6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B6B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1