Malicious PDF — malware analysis report

Static analysis result for SHA-256 23a88e4d474e49a3…

MALICIOUS

PDF

81.7 KB Created: 2021-09-21 00:26:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: dafee054398979109be527d7cf94b2f0 SHA-1: 87c66330f9c5f5a202e3fce6a0b0aaa8e32eb171 SHA-256: 23a88e4d474e49a3f791bcffefe59c6b14d7feac94d1f6ec281335cb91bf2c20
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of external URIs and link farm heuristics confirms the document's purpose is to lead users to external, potentially harmful, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://krisoc.ru/uplcv?utm_term=nba+2k17+apk+obb PDF link annotation
    • http://mosvag.ru/img/lib/file/6112034951.pdfIn PDF document text
    • https://guanlai.tw/uploads/files/202109100306025919.pdfIn PDF document text
    • https://xinpayflow.com/ckfinder/userfiles/files/nubavibaxal.pdfIn PDF document text
    • http://gonzagafood.com/userfiles/files/59089475519.pdfIn PDF document text
    • https://alteanetworks.fr/img/file/favidujidepi.pdfIn PDF document text
    • http://okun.su/upload/file/fedezexigilipanileja.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/7241ae1aa1a455cd3489a73caf912e15/kugapagofijonokesiratanoj.pdfIn PDF document text
    • https://thebookonpersonaltransformation.com/FCKeditor/file/zafajewe.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/56781899709.pdfIn PDF document text
    • https://hyundainhapkhau.vn/upload/files/kegefi.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/66107362975.pdfIn PDF document text
    • http://bulgankhangai.mn/userfiles/files/gobilep.pdfIn PDF document text
    • https://vonia.mikludava.lt/images/files/domisapisinezuxok.pdfIn PDF document text
    • http://tainanrup.longi.tw/uploadfiles/files/20210917_122358_4863.pdfIn PDF document text
    • https://middletonchambers.com/ckfinder/userfiles/files/54037695631.pdfIn PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/zolejedemum.pdfIn PDF document text
    • https://ngonluathan.com/images/ckeditor/files/vofilod.pdfIn PDF document text
    • http://kwiatmetal.pl/userfiles/file/74727204092.pdfIn PDF document text
    • https://childprotectionindia.com/lexcyberia/userfiles/files/65455326788.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f61c612122---depolite.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16135acfae6667---todinosotinujujit.pdfIn PDF document text
    • http://quatangsongvan.com/hinhanh_fckeditor/file/sozikox.pdfIn PDF document text
    • https://grouptm2.com/contents/files/xunagenipide.pdfIn PDF document text
    • http://mrpennarak.com/user_file/file/23177857151.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_off0000e05e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE05E 9936 bytes
SHA-256: 53fc2adf7574e8b8e14ff52d965a18b8dfde608b660938d91aafb85152809c72
font_01_sfnt_off0000f65a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF65A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010e6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E6C 16672 bytes
SHA-256: 0194eb8d2983debdd0fe17ab308ca2b96a587ba1d371a4f8375828f55f0d20a2

Open this report in the interactive analyzer, or submit your own file for analysis.