Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6cf4f6c4840ba2b…

MALICIOUS

PDF

77.5 KB Created: 2021-08-22 00:36:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 00d8a599bba01401f78235f891b2cbb2 SHA-1: b2acdb1a522e90839438e3b10ddfbf98436f3a1d SHA-256: a6cf4f6c4840ba2be0c844e6cad396847230513d9d53a271681b77433111b0b4
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, with the primary attack pattern being the exploitation of user trust through malicious links. No scripts were extracted, limiting the analysis of direct payload execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/88d16f98162ff03908769d2ee8b9746f/wufiwolutex.pdf In PDF document text
    • http://flirdining.com/uploads/files/winadujisawixilubinem.pdfIn PDF document text
    • https://mobiligennari.com/userfiles/file/tateziw.pdfIn PDF document text
    • http://www.retorika-zidar.si/ckfinder/ckeditor_uploaded_files/files/90865048267.pdfIn PDF document text
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/e7cfb1923b0f01c497b24568264739b0/86582458925.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086f22fabe22---52286249582.pdfIn PDF document text
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/2366d08f37ce7e5191bb9cd12dea0cce/23903234865.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fae305a76e---55049347741.pdfIn PDF document text
    • http://backkwang.com/userData/board/file/povemipulexosiwo.pdfIn PDF document text
    • http://extracam.es/app/webroot/arxius/file/kovilijolovoxexupene.pdfIn PDF document text
    • http://mp-journal.com/media/file/76357997085.pdfIn PDF document text
    • http://dentish.ru/ckfinder/userfiles/files/33995136590.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b335ced2fb0---memokilorilinato.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/01bf2e16f510c2681eda734824252cd5/xikadexagugulojagoguje.pdfIn PDF document text
    • https://penzionradvanice.cz/res/file/2306688736.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/e7fdde98bba86af7383954f15052f61b/34808429513.pdfIn PDF document text
    • https://abeess.com/userfiles/file/92634264576.pdfIn PDF document text
    • http://seamacros.com/upload/file/96164440661.pdfIn PDF document text
    • https://thepainter.asia/upload/files/gagibumiwe.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/9dd228e1269986e80473156a8e03722e/5580238222.pdfIn PDF document text
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/robuxegeligu.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/83588706837.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/bidigevipodewavuwowinomud.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/07-17-08-42-04-82.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=libros+de+medicina+download+pdfPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000caa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAA9 10868 bytes
SHA-256: e2616120a652fd1f7c7d8a5e8aff97eedc502b5e6fb76a731359f066cca18dbc
font_01_sfnt_off0000e38d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE38D 17568 bytes
SHA-256: 94ff64fb20eb12462e6fd497e4de6e049167c8e029d2f20377e29a31357f8002
font_02_sfnt_off0001106f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1106F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1