Malicious PDF — malware analysis report

Static analysis result for SHA-256 de3d5124bc32a3d3…

MALICIOUS

PDF

68.7 KB Created: 2021-05-10 03:07:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: c16edb41b3cbe31e285fb3d22d8c23eb SHA-1: a00e75298e203a690476f53cb8bbd0c265eea648 SHA-256: de3d5124bc32a3d3ce3f8e629395228b3c04be28e54d24279cc6d501a2039fe9
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites, suggesting a phishing or malware distribution campaign. The presence of PDF-specific heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' reinforces the attack pattern of leveraging compromised infrastructure to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/a31cc9b925f936c7d67a7b08f011ea38/xirinimo.pdf In PDF document text
    • http://axwelindia.com/uploads/kabimut.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/bb609dcd3e3efc1fb3921e893eb2e1ce/7288409534.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/92cdebc156719e1e5c27adadbef5df1f/10244778462.pdfIn PDF document text
    • https://healthcareadvisorsgroup.com/wp-content/plugins/super-forms/uploads/php/files/t9qve5r9ej4l6o8kt1dkcunb54/54880883596.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/63fd811a3c55f5b56698609944ca74d3/27367051502.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16070511d3f842---kudidotizugojenokumabe.pdfIn PDF document text
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/8gdq9m0qmpvrboqvsdv1jvpvvb/zifer.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16070709e28495---60090728391.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609872573f39a---zedezamowafabofa.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/ub51kp3lbrmqtepj20v56p23n6/geganoju.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/12950721391.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/39ocls6nun42j46iu6ahbc4087/77248304691.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743662c3903---61220036117.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/eaedf0f554cc986ec02fe0194bf60df8/pomajor.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=html+bootstrap+navigation+bar+templatePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ceaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEAF 5300 bytes
SHA-256: 0f97c6a64fe0686994e558fb78a5679125f9c8470588cf34d99c6b5f9574cda7
font_01_sfnt_off0000e0a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0A1 10468 bytes
SHA-256: a84feea0d4761d58f9879887b569da1c99d5c380df5c2424461c0ccb452c6831