Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdba9cb20a249b49…

MALICIOUS

PDF

83.7 KB Created: 2021-08-17 02:27:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: c89678bda733167792efe2d0cb8f90d5 SHA-1: 9f24c11504dabfef5ec629445cfd571214604866 SHA-256: cdba9cb20a249b49b579d257369f4f7c16519438bbd31a068a80b7394efc424b
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content or phishing pages. The PDF structure itself does not contain readable content, but the embedded URLs and heuristic firings strongly suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

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://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/m1ehd7s3djl7re0tmt4rj3afv3/wanuraterax.pdf In PDF document text
    • http://www.radanhorse.com/resource/files/58275051302.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/71s8mjq6fvb4i3de3cr0ls1m61/piniruxosoremujulozed.pdfIn PDF document text
    • http://krikrik.ru/uploads/ckfinder/files/57379747827.pdfIn PDF document text
    • https://cr2tek.com/userfiles/Proj_Name//files/79066208024.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ae7a99b18---rexijujifijamux.pdfIn PDF document text
    • https://interior-mark.com/ckfinder/userfiles/files/katanuwufofom.pdfIn PDF document text
    • http://b-solutions.net/userfiles/file/fuwusedi.pdfIn PDF document text
    • https://gitteszoneklinik.dk/ckfinder/userfiles/files/64091059014.pdfIn PDF document text
    • https://huaku3c.tw/uploads//files/202108120153523645.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608af9144a250---29821798442.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/63c36d3fdf954fa9e3964c4442fb6b64/44274711716.pdfIn PDF document text
    • https://pharma-tools.eu/galeria/file/fobagonirumasowazamad.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1606cca17e344b---deramipudulenowopimazesu.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/b11c1f16bb81eaf35cdc74bbb138d66f/13871144713.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/26552382182.pdfIn PDF document text
    • https://bangprice.com/bangprice.com/beta/cms_image/file/86960281265.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ee0dac64add---nuxatirum.pdfIn PDF document text
    • http://ttccid.com/userfiles/files/54438684834.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/160826ef2eac5c---21328558548.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/reguxezeruwepem.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160a024f6cb4fc---11873533637.pdfIn PDF document text
    • http://daltan.hu/userfiles/file/70483322389.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea7eb216ad---getivasanobutisuxasiwufi.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/l6e3tv8j5kkhh85qrcnpc58rnt/didij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=lista+completa+de+verbos+en+ingles+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_off0000db7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB7C 11128 bytes
SHA-256: eabdc6d5a609e4897b1a5b0d8fa11c7eca39ff039bd3d2e2c507f6db13789a70
font_01_sfnt_off0000f50c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50C 20080 bytes
SHA-256: 3ba27f90579a44fb5e9a9c72c8d8aab46f8b0d41a186f05a7dc9f8c5e0b92049
font_02_sfnt_off000127bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1