Malicious PDF — malware analysis report

Static analysis result for SHA-256 c10c0e66554ba4e8…

MALICIOUS

PDF

88.1 KB Created: 2021-08-04 00:42:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c6c6e648535e5cba91efd6d519e5de16 SHA-1: 4dd94c921f69ed57b57c61bee0003a9704599e60 SHA-256: c10c0e66554ba4e81120162a4a6eb5f8bb2aba708808b07d2c8e7b37f4fab48c
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Numerous URLs were extracted, many pointing to compromised WordPress sites hosting PDF files, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3895bb0a8f---77062116499.pdf In PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/l6a0dtafg8jl6l008qgd21c9o5/24063751353.pdfIn PDF document text
    • https://cam-ceeds.org/ckfinder/userfiles/files/wojupozogejadupevedazufo.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091686a1e82c---29493734471.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/bbe57075fbe0062dbb3a01388e00393f/90282796834.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a448e084821---14959432067.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/d9804c121b41a9fe94f73cf471ff60b7/fumuvesisus.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4f0ac4d7f8dff03627008522ccbc7a4f/fofilizimexigakorixixopum.pdfIn PDF document text
    • https://yucekalipmakina.com/tsrm1/img/userfiles/file/sarexowilip.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c7afc8a28---8599681389.pdfIn PDF document text
    • http://amouage-salon.ru/admin/ckfinder/userfiles/files/sugutel.pdfIn PDF document text
    • https://giritrademark.com/content_files/files/gusaxumutikikexak.pdfIn PDF document text
    • https://dentalrud.com/userfiles/file/wemibegabezipu.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/pt2uu577u1vsohch2mvfd3ms97/ninoduwegaxijufipi.pdfIn PDF document text
    • http://daindnc.com/fckeditor/userfiles/file/58912662314.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084986b99a28---mawaxep.pdfIn PDF document text
    • http://effektfilm.de/files/file/71069967449.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/2dfc0a6c0f02d714090aaa424adb1e55/20400073546.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ceb6f07b9---podefodavudovapizegiwe.pdfIn PDF document text
    • http://cssh.es/img/file/36655469262.pdfIn PDF document text
    • https://best-label.com/upload/files/44272409274.pdfIn PDF document text
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/11762093310.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/u5jvb8u4p2odrj3pefukfcgam1/zigiwenenamazelikajuz.pdfIn PDF document text
    • http://serting.eu/userfiles/files/22029054129.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b013842db32---29770828041.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=what+is+consensus+theoryPDF 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_off0000f61f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF61F 10488 bytes
SHA-256: 94a40a9e1b2301ac3e6f36e8f264cb31038145fc4d4f70c0870cd84bf818677b
font_01_sfnt_off00010e01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E01 16968 bytes
SHA-256: 5459e9782da8db84efc3ad582e5c37baa2f14c945695e519c6b67dfd55db03de
font_02_sfnt_off00013a19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1