Malicious PDF — malware analysis report

Static analysis result for SHA-256 9dcf849238306e9f…

MALICIOUS

PDF

87.0 KB Created: 2021-06-17 10:58:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-31
MD5: 1f641f8496902d930bd605e1712c5660 SHA-1: e9eb02b8438d19bfc18c93090d342d0855948afb SHA-256: 9dcf849238306e9fec95a9427dd6c72b2ecaf7df66a62d52aedb298979533a00
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, indicating the PDF acts as a link farm to external, potentially malicious, resources.

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://queure.ru/uplcv?utm_term=street+fighter+1995 PDF link annotation
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/f487v7opklvth35qldmt6pcquu/daloxukilumi.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/13103970330.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/ef1e232893f2a13320efcb3a9ed0daa0/riwogabix.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160c54495ccb3b---lurejavuzepuw.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608f2b5291ae2---37522263217.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a13372205ef---46057156079.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9ea42cf9d---mitigolulogiwovotodibiw.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/e27b16e48df4ff4c99ddf92459634831/xekovobuwafadesuxoveki.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/ca58ec36566073d88d871f4c6fef92a5/zinokibibope.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/3sakfd70vqh2qrdhi54a1mapo8/bizelukisi.pdfIn PDF document text
    • https://bilalyapidekorasyon.com/userfiles/file/21244559019.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3691d94448---nuwenusigegenixirute.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/737aad5c8925bfc0944335407633df82/safekevetanir.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/79374494370.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_off00011516.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11516 5044 bytes
SHA-256: df98c17cf489f4776abf4abbad462e7ec5ca4bcfc0c2273f505524279e6b88ea
font_01_sfnt_off0001264b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1264B 12500 bytes
SHA-256: e63a4e58aedb9eb464599ce4b139d528c47945881d7b7e9da37ffb048999723f