Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bdc31aa58676598…

MALICIOUS

PDF

89.4 KB Created: 2021-09-06 10:49:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2157e11a0fdbcbcfe8bf48d5d2f85557 SHA-1: 6c00cf4f1885a8a1d37d7f8989f97def8e4d7249 SHA-256: 7bdc31aa58676598476f70f307c9d6ec20c546fc7c4a21298b290468636a0a8f
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external PDF files, many hosted on compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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://doctmcooper.com/userfiles/files/gijupirowimim.pdf In PDF document text
    • http://mylodge-naoshima.com/images/blog/file/56578094428.pdfIn PDF document text
    • http://lanaecoloridabruzzo.it/userfiles/file/42089491872.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/13e056fc35f55f37c37e0e21948b428c/wowodam.pdfIn PDF document text
    • http://ipceurope.com/assets/file/ribakirizizebowanur.pdfIn PDF document text
    • https://www.premiumtrade.ro/ckfinder/userfiles/files/zubenijes.pdfIn PDF document text
    • http://gorillatheory.com/admin/upload/file/95086634294.pdfIn PDF document text
    • https://dodomacnosti.net/data/file/99938673233.pdfIn PDF document text
    • http://101balkon.ru/upload/files/58026924594.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095f9ba68189---rojutadedawajuwutivawe.pdfIn PDF document text
    • https://kingwrapcarspa.com/upload/files/24067411888.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/18f8090b6394ce2ca89691eabcd06e81/1399987811.pdfIn PDF document text
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/002c6ee403a6be57195b4fe77d2e6bdf/sizogenowunefasevoxu.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/rifukesikadu.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/nuwodilokaka.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/1b181bd36b73936e4986443e6af24aec/21130657615.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161219a149847f---nurezojokuwolutukumizur.pdfIn PDF document text
    • https://valubil.com/public/uploads/cms_file/cms_files/36471330597.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/26648f157b8aa2381a74e88af70469ec/41494154127.pdfIn PDF document text
    • http://xn--h49al71atridzo.com/userData/board/file/17142075260.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a766ab1ddf3---masojutadepukunofavu.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608f12b480762---80934375814.pdfIn PDF document text
    • http://maisondequartierdespareuses.com/userfiles/file/11542428390.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/36261960391.pdfIn PDF document text
    • https://fullhousetourism.com/UploadFiles/file/20210807224439184.pdfIn PDF document text
    • https://www.bnbtravels.com/ckfinder/userfiles/files/216893169.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=ncert+solutions+for+class+7+english+honeycomb+chapter+6+pdfPDF 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://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_off0000f3fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3FD 18636 bytes
SHA-256: 65695390d93dd0cd9bba8c90f93121a265a6513f9669b1fdf5610751f64cfc75
font_01_sfnt_off000123ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123CE 11616 bytes
SHA-256: b26747dbafa7dd6b4e78d15c6800717287b2dd8b73b5d7e0516cd642b0ccf3e8
font_02_sfnt_off00013ee2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EE2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1