Malicious PDF — malware analysis report

Static analysis result for SHA-256 141b5210ed9d6ae5…

MALICIOUS

PDF

79.0 KB Created: 2021-08-27 10:35:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e34a210bb8844e70bff63a8068cef1d9 SHA-1: 6e3f6cd935d4f9e1746c0da3acb844a7725c5260 SHA-256: 141b5210ed9d6ae50bd097c0a537f7d5d7aafcadf1ad82cafd902338d8b46d6d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content or phishing pages. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating the document's purpose is to host a large number of links on potentially disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://archism.ru/uplcv?utm_term=how+to+create+a+fillable+pdf+in+word+2010 PDF link annotation
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/8ce837m34surgou1vrlu4k5uq3/podasogagugagofogovugumi.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/c20bafe8fbadfcc53ecf6fe6b749661b/kepumuromovufigugem.pdfIn PDF document text
    • http://greenlivinggarden.com/htdocs/UserFiles/file/woligipaxurefuposoletob.pdfIn PDF document text
    • https://aashianarealty.com/file/4843923668.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608599842abe6---97248727830.pdfIn PDF document text
    • http://orsini-blasioli.it/userfiles/files/57442113304.pdfIn PDF document text
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/cc7d7a5e5c02f95ab521cc4aa2c1f6ef/kopabopusuvirujem.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16098b1179e8a8---ripixofewol.pdfIn PDF document text
    • http://someteme.com/archivos/_20210721165016.pdfIn PDF document text
    • http://uralinteh.com/uploads/files/suleletuvusiru.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/o3f37c75mlqqqt38s4qovs9m84/64269491796.pdfIn PDF document text
    • https://educhina.mn/editor/files/15236331147.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/jutososogukon.pdfIn PDF document text
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/zimugikevof.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/43807638825.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160b2937209641---xurinenode.pdfIn PDF document text
    • https://codecs.ro/images/file/dolisimuvelesujikefexiwib.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/68508601965.pdfIn PDF document text
    • https://www.burnat-provins.ch/ck/ckfinder/userfiles/files/terogowixodogokugeb.pdfIn PDF document text
    • http://nwatchonline.net/userfiles/file/wujepevutefitarekopok.pdfIn PDF document text
    • http://ozona.pt/wysiwygfiles/file/6556233678.pdfIn PDF document text
    • http://picassogift.com/Uploadfiles/files/63972392366.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_off0000d1a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A4 16348 bytes
SHA-256: d8f60e2ff7ab55fc835d2f4273c08745b8ad41e30262e0e972529132ee050343
font_01_sfnt_off0000fbf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBF3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001140a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1140A 10956 bytes
SHA-256: 46c14a72f76e22099f292de5b83e05c85bbb60fbb79b64726a6b1c0d3d9de581