Malicious PDF — malware analysis report

Static analysis result for SHA-256 a583a559513d9a52…

MALICIOUS

PDF

76.5 KB Created: 2021-06-23 01:28:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: a40bc8bf04b00163979a17c58398f52f SHA-1: 4c79cecaf90530cec3c6d740a9b008d725f42284 SHA-256: a583a559513d9a52f600fa8d86c09d9b703cc71231b722b1ec87c45f33c83016
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

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 http://jrpst.pl/userfiles/file/95479368089.pdf In PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/9b80db7e9864d9d85ff48c3f945fcff7/1293413861.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/56f839f1cf65a69ed6dce5003378055e/samomodefibilonigur.pdfIn PDF document text
    • http://rideco.hu/upload/file/33436710845.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210621035703_nijxf1.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/f4d91b16571838ab746c5441b6fbfcf3/59969640543.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d8f4592b9---10901409979.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e87990b60---7452550120.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/17144331958.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1108a4647---52795320332.pdfIn PDF document text
    • http://ofipapel.org//ckfinder/userfiles/files/90364506435.pdfIn PDF document text
    • http://paitoonbox.com/userfiles/files/20003043631.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/ed82006528d010f49916eb43bb35f046/wudokirixeji.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/25c2b2625a72abc8a5fbf770fb6c2c5b/vaxezumog.pdfIn PDF document text
    • http://mtcongnghiepxanh.com/upload/fckimagesfile/boxiganenaduluk.pdfIn PDF document text
    • http://unnatiwelfareorganization.com/ckfinder/userfiles/files/wijojigusomip.pdfIn PDF document text
    • http://apluskleaning.com/admin/images/file/98651528819.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/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=is+hydrogen+peroxide+and+yeast+endothermic+or+exothermicPDF 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_off0000ecb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB1 5560 bytes
SHA-256: d0165a70a39a43119de8088fe4ad231a86f9dce1dca11064cde4b9c69d583883
font_01_sfnt_off0000ff83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF83 10708 bytes
SHA-256: ab1c0914f9df1c9ef585201ffa64128a53a748beb837265f8c57e6983b2c7a85