Malicious PDF — malware analysis report

Static analysis result for SHA-256 43586a674173b06d…

MALICIOUS

PDF

69.1 KB Created: 2021-09-27 02:11:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e07f45dc0673ef681f21d3f4504bccc8 SHA-1: cbcd1fa591cdf7ff9172869bfb777366e89c8dc5 SHA-256: 43586a674173b06d16725dd07a56c914f4ef9a66e45efacaa6796bdd89dac65c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting a phishing or redirection attempt. Although no scripts were extracted, the PDF structure and URL patterns are consistent with malicious documents designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://struttur-arch.it/userfiles/files/fuweburoxumilaziwuv.pdf In PDF document text
    • https://dispecom.com/cms_dispecom/sgi_userfiles/userfiles/files/93647613081.pdfIn PDF document text
    • https://egf.tw/test2/images/file/febepakasem.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210913172529.pdfIn PDF document text
    • https://elitstroycraft.ru/source/file/7809640947.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/mafuteb.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/93453905033.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/35682467915.pdfIn PDF document text
    • https://afgventuregroup.com/cfiles/file/fenajagusedutijitojofi.pdfIn PDF document text
    • http://nbc.ua/design/pic/file/86974853395.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d042260a00---10060030259.pdfIn PDF document text
    • http://exclusivelimoservice.com/ckfinder/userfiles/files/keronizobudizuwuxip.pdfIn PDF document text
    • http://islaminkiel.de/webmisr/uploadwebmisr/file/93334601057.pdfIn PDF document text
    • http://fruitvita.com/files/files/jebudisak.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16149cfdac5909---10956316691.pdfIn PDF document text
    • https://www.kuwaitpolyurethane.com/ckfinder/userfiles/files/pegulefi.pdfIn PDF document text
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/f9pqsmvp1au9kf97nj1rv3qnm0/92355526959.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16137d91f7bc8b---13470765318.pdfIn PDF document text
    • http://timebymtm.com/upload/files/wulifoj.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/surolizetexajenapax.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614117be93a83---24159490608.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=qikshare+bump+airdropPDF 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_off0000accc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACCC 10800 bytes
SHA-256: c0e236ef6f2ccbfea07dd7a4a20cfb597fa9e8dbe95de8c3f1ab35816dbfbed8
font_01_sfnt_off0000c580.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC580 16128 bytes
SHA-256: dedc954b5ee3b855086224055396643ad9e35096285ad4cac8f2d3166e72bf29
font_02_sfnt_off0000eef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1