Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3d537b85f2a13dd…

MALICIOUS

PDF

88.3 KB Created: 2021-06-24 18:07:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 9a980177c6415127a7a1b62c0501f9a3 SHA-1: 673bd4186b1f4234b7bf3f980d66415a4d67a185 SHA-256: b3d537b85f2a13dd05cf74c54ba03169aef2b242a786ebac103e6af99a0b7966
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised websites, specifically leveraging WordPress upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link farms, suggesting an attempt to obscure the true malicious destination. While no scripts were explicitly extracted, the nature of the links and the detection suggest the PDF is intended to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/258c120ecaf1401247c07325e37ca765/60311052714.pdf In PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/71e96b74773da77a2cdad721fc1592e7/60666824815.pdfIn PDF document text
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/55d2bbb0c9e871722277793259cc35a3/6627888627.pdfIn PDF document text
    • http://sushinamu.com/uploads/files/77770960136.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/6915619ef4ecc067607ac87a3da7a58b/nuzuvorok.pdfIn PDF document text
    • http://highlandhighclassof1962.com/clients/c/c3/c330a44b04b080977bf299ea430a317d/File/59074455523.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/7a46aaf2b234e58ae6b636fec9ee826e/dejexijaju.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/27599631772c1d3dab72dcd5efe298fd/musikiruguzatamutemo.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c230bb1903b---71244336962.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609f326812bf0---kebojerefokijonuko.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/97015873979.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/bujemagarolokema.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/3c217b2b18540a229e46cd424e09935d/gunoruzerowum.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160c8a746a9297---3637454546.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/jigavilunipijotan.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/9bc93a2d568a8b0564cb6f900004723b/71326232831.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3d8f77fa2---sujabiliger.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a6837c0c0---72809757491.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/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=ap+calculus+related+rates+worksheetPDF 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_off000118c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118C8 5308 bytes
SHA-256: 520065df8d5f3cd9c643e7f73537ccc6700720eee5fd8e90b4a1eed16ed524af
font_01_sfnt_off00012add.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ADD 12372 bytes
SHA-256: 84f6dc4445e3d766f858d3355d264e93325e274dc3bd8d2e7446057567fc223c