Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5f9bc8bdcf11041…

MALICIOUS

PDF

71.8 KB Created: 2021-06-19 04:56:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 126500ceaae71fb24ccdd06dc30b3712 SHA-1: 8f0f8603ed8e12c1e388c358555de0a68f06eabc SHA-256: b5f9bc8bdcf11041d118c0fc1c9d69e6d46dad2c157031f19f47a34133d7d72e
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://wingprocess.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zaxotetu.pdf In PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6993543c4---97631595994.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/16099f5c01c0ff---87441311314.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ccdc7564bf---54037828360.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/11494012525.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/r83kbm6gm81129leiet4q33ff7/60457769915.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/45ii5evs7s3lqpvu2iikv9ckh8/46258536143.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/45a4733a5c13dbedbd00a18056a93b4c/28300060920.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/d27e6f137c168a2030094c178bd5bd56/piwipajudewini.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607f135f4d6b1---45065874765.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/4a66b253426c70523eff55c6be6ca351/wosaxuwejegenovepelumoni.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/lomutoxobivumolalakar.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/0c754e609c693c809de71e4fafcbb6f9/kotikatidasevuvebabexifoz.pdfIn PDF document text
    • http://geoodwierty.pl/files/file/karoba.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/~3/3CAf4wW3hvY/uplcv?utm_term=animal+farm+pdf+bookPDF 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_off0000de10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE10 5200 bytes
SHA-256: 582f48a2ca74c1633504e8adf35253ff5ca7891acbf9a986d6cf91643e79da35
font_01_sfnt_off0000efa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA4 10364 bytes
SHA-256: b0d72c3285c37633d5d2641ba5b061352351a7d386a64eb1e1475fb69376f9c7