Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b87ab3732b8bd21…

MALICIOUS

PDF

65.8 KB Created: 2021-06-12 07:46:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: bc48e895f7f265de7fb52e1e20d4d1cc SHA-1: 3e40185ca9c3cb73bd3a5461cda6b4738dc433d9 SHA-256: 9b87ab3732b8bd215581193fce344f907d14f5c1afecae9c464ef92d10d2f25c
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV. It contains numerous links to compromised websites, suggesting it is part of a link farm designed to trick users into downloading malicious content. The presence of a 'download button' heuristic further supports this phishing and malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • 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://crewmak.ru/uplcv?utm_term=five+nights+at+the+krusty+krab+download PDF link annotation
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160adc37baed2f---siponisiserobegifuv.pdfIn PDF document text
    • http://longarmacademy.net/fckeditor/userfiles/file/5051597889.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609f97868e3fd---28858700415.pdfIn PDF document text
    • http://armanetti.com/images/jivuxikudozi.pdfIn PDF document text
    • http://gewoongroen.eu/app/webroot/files/userfiles/files/73896972735.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094b95e7ba4d---luruwiwafuvujo.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160877552d8120---2491503954.pdfIn PDF document text
    • http://www.tecnobor.com/ckfinder/userfiles/files/19920588458.pdfIn PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/07c47d24eedc4888f98907e91a145409/89870303166.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/72327239962.pdfIn PDF document text
    • https://mosallaesf.ir/uploads/ck/files/zefimep.pdfIn PDF document text
    • https://ols.lighting/wp-content/plugins/super-forms/uploads/php/files/87c8cc697fca657011340baa6b9844dc/81264094118.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/7981340182c2af5c9c8707b1e17d9b22/42394966971.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/rv4i8pttcplicpfv9h62obd1nb/36806851887.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_off0000c599.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC599 5500 bytes
SHA-256: f836787e0da621740b4581ab782e88241379ca2fc569778d72c141edeac710d0
font_01_sfnt_off0000d863.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD863 9940 bytes
SHA-256: 4a22d44b7cb62c4a080e96267edd38b48172c1cb069dd33b254080e301c65574