Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b8cd4b52cc166e0…

MALICIOUS

PDF

65.8 KB Created: 2021-06-03 03:38:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 65a1788d973ac1d6fda791db10c73d15 SHA-1: 07e63faa6e3e330bbbc65f32e718186e585a6683 SHA-256: 3b8cd4b52cc166e073940ee63f8e3f606ce5c55f81fe982d54d6c26942a9cf78
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS upload directories, suggesting it functions as a link farm to distribute phishing or malware. The document body, though heavily obfuscated, appears to be a lure for educational materials, aligning with common phishing tactics.

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://crysiq.ru/uplcv?utm_term=benim+hocam+video+ders+notlar%25C4%25B1+2020+pdf+indir PDF link annotation
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/b0d40d45f2d10ebdce42febb419393d7/gafopuxibobirawazi.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/1kbef9phb7fjg1srgc6knfbs2o/begokaraxixim.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/nvb53vh4q040f95c766u4da8up/fudotabewiwefudagapuzal.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/56uibp9s0sateme67ludrgqr34/rikobiguli.pdfIn PDF document text
    • http://vote4dannybarry.com/clients/2/2f/2f5d4f67c16906f9b09010289963de11/File/vaxawizimelik.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/0c4629f31177b225a6fb9c989a093fb6/83866713184.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1e6560766---19790218629.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073d6ecb5950---bejuxagumu.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/a38641041f80b50583429601f71da26f/xujageti.pdfIn PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/o260qpctu7j1orpct6a6b28bk5/zevugumonorudexelikamag.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/mibiwimosotusomeroz.pdfIn PDF document text
    • http://stevis.cz/files/file/52406363277.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/renuwikomejamopa.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/afc08aabf4f33a23a49da8a501bc8f11/buxufikusipalulowomoju.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/346ec3384480ae801b0b6033cd91e9f9/dosebamorejevimezi.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/72085764205.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_off0000c1be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1BE 5812 bytes
SHA-256: bb862456eb7b58cc333ff3c8af6c5eede2cb2a5cb3b680f048268987c1211440
font_01_sfnt_off0000d563.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD563 10772 bytes
SHA-256: 0ca8abcc602adbeb196f5e7b8efd0c804defb567d2e766b7c13ef89df04a3bf8