Malicious PDF — malware analysis report

Static analysis result for SHA-256 c820650607d87887…

MALICIOUS

PDF

90.6 KB Created: 2021-06-30 23:58:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 85f8fd8f4818bdc43d8eb54a7a62e903 SHA-1: c6e5cd8d7d01ef74d05f06a3b8ccd8f41971a10d SHA-256: c820650607d878877f9148fd7e2c64560270c4673292a42d59dcc6268e4ef7e6
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. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were extracted, the PDF structure and embedded URLs strongly suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8f1fd4bd5---newanuwadepag.pdf In PDF document text
    • http://unnatiwelfareorganization.com/ckfinder/userfiles/files/66170196638.pdfIn PDF document text
    • http://ascensionchina.com/userfiles/file/96185492941.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f339f731f3---nufamiluwokefowurejaxuvol.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/50981426392.pdfIn PDF document text
    • https://www.tanyadantus.com/wp-content/plugins/super-forms/uploads/php/files/a356e5f9e05af806c1e904364b60243e/wefiwoxedidetubolodeg.pdfIn PDF document text
    • http://aj-logistics.com/stock/userfiles/file/zorufosufa.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/01094355737.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160aeaa1bc9026---loziruzisupibonixilurap.pdfIn PDF document text
    • http://contelex.it/userfiles/files/pidukox.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/lvid07g45mtfboe0btfvn1vbou/bosofuroperodul.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/48827312664.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160909d6344174---56779725553.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/43790df6615e330fd1ebc1da605aadb1/19142452861.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/65540308470.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/304141cd0816d75d73e69885156aae69/66875077963.pdfIn PDF document text
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/aa8fab9c647c6c200d5a5e045144fc48/mogivirutotavuwerakifom.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/6fe34ab157faa9b3fb9d317be2db9c39/gedaxopanu.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16088e8115d55c---26595110967.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/67dasfpi36jss808akdlc5ad59/84232066530.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c03a15c2054---87410993635.pdfIn PDF document text
    • https://bandai-k.com/userfiles/file/67190850008.pdfIn PDF document text
    • http://gospel-pour-100-voix.com/fichiers/newsletter/file/lofetaxet.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ce9c4cefd---jozeliwojifavepuzuxor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=porter+on+competitionPDF 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_off00010128.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10128 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001193f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1193F 10160 bytes
SHA-256: 43f9d01c2cb964ff67393a75004a72b2cdc2b89510ac51e040ebaa8e89ab61af
font_02_sfnt_off00012fe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FE7 17376 bytes
SHA-256: 8701ffd51036c1b4f11abc1d53e84293b3a60605ab87a79412a9b40a98ae8f7d