Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f651c4de130ebc8…

MALICIOUS

PDF

82.6 KB Created: 2021-06-15 22:19:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 21f589e070248830aca45c7235dd5ea7 SHA-1: 5a3febcc8a5ec3068d01abac9c170ad4aa1261ed SHA-256: 0f651c4de130ebc8ecb1546232ecb6fcc96433e7a0207748e0fe3b7c69c8d902
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm designed to distribute malware or phish for credentials. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan distribution. No scripts were extracted, but the presence of embedded URLs and the nature of the heuristics point towards a malicious document designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://chcial.ru/uplcv?utm_term=definition+of+external+conflict+in+literature PDF link annotation
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/e7fc4d5170c3959a85297e03f499ff00/26868670671.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098634893cbf---10911755515.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a8d6669f46d---56773985800.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/igv1k5dfviktif4u0slv0fu39h/73958098252.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/591e6a9f2b9ce8bff437ef18168a95b4/sapagotuvixejagajugaj.pdfIn PDF document text
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e3af04fd00---57007342211.pdfIn PDF document text
    • http://tz5168.com/uploadfile/image/2021/05/13/file/20210513_124259_199.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/mumebobaxupimi.pdfIn PDF document text
    • http://bmhs71.com/clients/c/c9/c97ff408e01126d63256cf68004d6641/File/ropefotoniw.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ee82a9b770---zirazele.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021052111344710.pdfIn PDF document text
    • https://llsindia.in/FCKeditor/file/83760063235.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/oclvkrsjc54tntirk83nefr504/44438090009.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c20bdee0044---xawig.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/99a956d6879ce5b8a1f319ec33a320c3/95130562493.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/2a2f1f4df0477e05c3cb2e282dd2127b/zawiliva.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/40d33bdd6b6e06ea03d48ca74628147d/remipitemuxujibuva.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010635.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10635 4764 bytes
SHA-256: af5add56b6f93452299eb9ab9a2515796791f036faf34cd7daf9e6d7aa89a6e9
font_01_sfnt_off00011684.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11684 10892 bytes
SHA-256: 6450eef076dfa70b8b2cceef0ed74a39c37a9f11afe54b26d9c5263e2e9b8580