Malicious PDF — malware analysis report

Static analysis result for SHA-256 c373d0b0b0ed1c29…

MALICIOUS

PDF

79.2 KB Created: 2021-06-23 18:04:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 8691e5e98d452bb2a1e28645c60d29ba SHA-1: f0acb0c33916e7c6e92a289e0343d761e7054544 SHA-256: c373d0b0b0ed1c298d6226f4b66442fe4f97cb098a97d06e96c8e70efa102830
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/22b8eb7c71690dd097a5c3524213055f/ximidigul.pdf In PDF document text
    • http://jrmhandling.nl/upload/file/87298780074.pdfIn PDF document text
    • https://gikguamerica.com/userfiles/file/najejudinajafi.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/7v9fedc46gl7e3avs52ufifc5r/84811718878.pdfIn PDF document text
    • http://mkngsp.ru/upload/files/48793397546.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/23716776849.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad77702f439---9934502694.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16073c3d047130---gadopasiwolane.pdfIn PDF document text
    • https://rebel-guitars.com/wp-content/plugins/super-forms/uploads/php/files/fa6cc6db2149c21a77bef1e50fdd95e1/tevijurese.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca2f456d1b---zuzizopu.pdfIn PDF document text
    • http://parkhigh65.com/clients/4970/File/45396570491.pdfIn PDF document text
    • http://backkwang.com/userData/board/file/86116195608.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/880629d03269d54b340a30cf1fea5362/juvub.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/uk8obgtg6n5jdqsllcbabn00l3/25951770904.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/vtjksdhcm49abfjqsd6od0l1u3/mebobafonokinomeledirivi.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/f66159509737363464850448c07d695b/84164892175.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/lonuvutojoz.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/~3/3vuEKuznOb8/uplcv?utm_term=call+letter+format+pdfPDF 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_off0000fa86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA86 4916 bytes
SHA-256: 20d424354d9316ac08e63449a877370a56a1c5f8b4938e832df6fdc2a66cafec
font_01_sfnt_off00010b23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B23 10472 bytes
SHA-256: 40cdab13c12e5beaf1e14dfb55f162a532cc4905d6e517808a5dba7f048b75cd