Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8957f64a4af445b…

MALICIOUS

PDF

91.0 KB Created: 2021-08-19 16:10:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7e359c8a684a262e05a420a693f80308 SHA-1: 795b9cde4cd59c7c583f507d7374ea4a49965b52 SHA-256: c8957f64a4af445bb079d7ae5b867dcdd7bcac998f9535f31fada65e3c05d2bf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were directly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/h51uk6fcncbo3n6ekjiqsqj8lm/zimusanidumijot.pdf In PDF document text
    • http://techcessgroups.com/userfiles/file/sominovuvuzipoxixeropetul.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071e60502df7---xerakodotajasi.pdfIn PDF document text
    • https://brahmagnanam.org/fck_uploads/file/ximotegibosi.pdfIn PDF document text
    • https://menu2uplus.com/images/file/ridaruxoresovidugiwex.pdfIn PDF document text
    • https://giridhareye.org/ckfinder/userfiles/files/43847056199.pdfIn PDF document text
    • http://zdravi-kromeriz.cz/files/file/pajozekulaxivitemujeb.pdfIn PDF document text
    • http://eko-gospodarstwo.eu/files/file/19895608847.pdfIn PDF document text
    • http://paroissedementon.fr/upload/files/naxutiwenafonerodiribubif.pdfIn PDF document text
    • https://perfecthospital.net/FCKeditor/file/dilabelanalasagisozuxuxe.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/f9b9mpiiuf1apccrbkoia3c5g1/52963398803.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/s7h9fc7h8flkkhg2ug0ek71o3m/12407324707.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/24701869779.pdfIn PDF document text
    • https://almuhja.com/ckfinder/userfiles/files/tivupa.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16094402d29a37---42597266037.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/files/62959992190.pdfIn PDF document text
    • http://alptw.com/images/files/pibewalajez.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/a267c05bbd088895ed20b903ff1213f4/sixidufiwa.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210710115001.pdfIn PDF document text
    • http://kayapaliinsaat.net/file/zajux.pdfIn PDF document text
    • http://csc025.com/userfiles/file/20210816035915_5zkwnl.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/0p39l3kko9go6frdv5640kgdks/38127548305.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=problemas+funciones+lineales+y+cuadraticas+3+esoPDF 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_off0000f818.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF818 11164 bytes
SHA-256: 332d258d36d608fa94836975f2203ba2c9a61c2c180abd64ca05997e640a0916
font_01_sfnt_off0001123d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1123D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A4F 19780 bytes
SHA-256: 0189c9a35e187edd39a76b29d1c594442be11c3dc76da3d941c41bc9158cb3b2