Malicious PDF — malware analysis report

Static analysis result for SHA-256 41c95bde9889518c…

MALICIOUS

PDF

107.2 KB Created: 2021-07-07 22:08:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 749d36f82a98a9fbf19684e79204e0e2 SHA-1: b33161b7c0400de5f3b995bfc4865f84e5265b92 SHA-256: 41c95bde9889518c96524814be070fba6246c0fea456a254ffda00b2a72da3df
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is a PDF identified as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The presence of these links suggests an attempt to lure users to external sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/c320209614d47b8ad4d2cb77c7235317/15033501686.pdf In PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad6f802c50c---19218838546.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/36660381900.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/ovcpg2cvb4qhj9sho9mg0inajs/viwepofuraromasobofike.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/gg3utrek7h2cjstc6mhs8157q5/rivuwejax.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/lagetikagotujole.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/70562127853.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8fafbbe99---57696756044.pdfIn PDF document text
    • https://thuanxuongmonmb.com/admin/webroot/upload/image/files/36314177264.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/g0k44igihbqitbifkpj5gp1ic0/xaxotab.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b4ce843934a---kotevoroludonita.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/2hrrvknd1tnlo8hilvbec80ogu/1370451913.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1607a216a9e18f---14699111943.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/vcgf38d212sq3cpckitop120a1/bebudupoponawate.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/bupizavowokuxa.pdfIn PDF document text
    • http://ergo-logo-bamberg.de/userfiles/file/mudolokobubopofanavamezu.pdfIn PDF document text
    • http://linhngapt.vn/upload/files/lejisuvo.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16091f0c7c9e0b---gotowizaguriforoti.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/vb3m2se2vkfhlerp1hql7uet25/kosara.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/f0bd4f0d75df5e396317c45172e68a62/47361712239.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608e291160d6a---52179022600.pdfIn PDF document text
    • https://plasy.com/uploads/file/sadifax.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/59a735e9ed9e93a8a4f0a3e1da717d49/55596420330.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/3305b0146b08bb116c0e4cb92f856382/bejilo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=the+book+of+knowledge+of+ingenious+mechanical+devices+pdf+downloadPDF 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_off00013b97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000153a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153A9 19984 bytes
SHA-256: b762083d6fa289951ff2b94453d744653d12182d9693295a6c6701e32bf92402
font_02_sfnt_off000184a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x184A5 11316 bytes
SHA-256: e560af5aa1545c1b27ad1442e0c1838e8f448461899bc7d96ec0298cbc9c8821