Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c6f55b809564536…

MALICIOUS

PDF

84.9 KB Created: 2021-07-17 20:47:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 248905c5807106f87ecfc494f34e4347 SHA-1: 123f89c8f011a13d86ec1bb67328f81732726056 SHA-256: 5c6f55b809564536722bf8910bbf3d464db7d0945fa51183dd079b0d32b2392a
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 numerous PDF files hosted on various domains, some of which appear to be compromised CMS uploads. While no scripts were explicitly extracted, the nature of the link farm suggests an intent to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://hndgyl.com/v15/Upload/file/2021625209495488.pdf In PDF document text
    • http://adria-ex.com/images/blog//file/26780548707.pdfIn PDF document text
    • https://ngaa.org.au/application/third_party/ckfinder/userfiles/files/jawagikikojiwu.pdfIn PDF document text
    • http://goopenapp.com/uploads/files/lobalatevepewej.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a379ef21f97---25683946986.pdfIn PDF document text
    • http://grubstreet.ca/ckfinder/userfiles/files/38987008968.pdfIn PDF document text
    • http://rosniyom.com/userfiles/files/dejexur.pdfIn PDF document text
    • http://cissi.it/userfiles/files/kolup.pdfIn PDF document text
    • https://hohsingfiber.com/ufiles/files/27760568089.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/k7rapjg6fbnlvtt5uemejh3dbu/78656372760.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a95308e28bb---giluketi.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/10868398538.pdfIn PDF document text
    • http://flagrant-desir.com/userfiles/file/tabevod.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce92bd8dc6---kewekaxo.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b66cb675fd3---zujasilogebozezig.pdfIn PDF document text
    • http://yangpupark.com/uploadfile/files/favujajijusigisuzebu.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160759d5fdf364---40997496280.pdfIn PDF document text
    • http://laptopcuhaiphong.vn/upload/files/xebemupoxikusalusakoku.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c03a6a5cf2f---biloxigotigipunogiz.pdfIn PDF document text
    • http://calzaturificiocatia.it/userfiles/files/zomixepelexuvorabagopoxas.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/033da87eb4fedda5e9f3c8c879df186d/duposoguriduv.pdfIn PDF document text
    • https://bonacorsi.it/file/48801265723.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a57b9725885---90837975310.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///46486005450.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/7bb38758a164b75daab9ce651891b4f5/bemamapa.pdfIn PDF document text
    • https://diarch.in/WYSIWYGImage/file/13690069031.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/d9f8ac8c59da5a40337eb78d8a446f56/fizujodutil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=the+tell+tale+heart+narrator+characterizationPDF 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_off0000eb60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB60 10184 bytes
SHA-256: d1746d0739f180f496b5e824b4f6d22d12087e811ef91f718be9fdf6081864a5
font_01_sfnt_off00010228.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10228 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A3A 16748 bytes
SHA-256: 2325ffad22f50a261a1b786bf31001aaeea2613a5c80aef53b9e0ce0cf8bd6b0