Malicious PDF — malware analysis report

Static analysis result for SHA-256 281691764ad48382…

MALICIOUS

PDF

82.1 KB Created: 2021-09-18 13:23:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a5df7240a1a26d65327b1540efde0d12 SHA-1: d39232be135651b2525150dff8305607f1e158e1 SHA-256: 281691764ad483822556cacd38ae9e9c38b6832e5904e0c2a4bd6e4668a6579a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to multiple domains, several of which appear to be compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 7

  • 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.
  • 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://ateliersmq.com/pevron/www/img/file/21965407287.pdf In PDF document text
    • https://ibliberia.com/ckfinder/userfiles/files/74157115780.pdfIn PDF document text
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nebevexakisare.pdfIn PDF document text
    • http://matchonusa.com/uploads/files/poporemenalefugaledipipip.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/dixexuwomujanaxuvux.pdfIn PDF document text
    • http://alacartedesign.de/userfiles/file/mumilidavumorirug.pdfIn PDF document text
    • http://drsuthichai.com/userfiles/files/93579390556.pdfIn PDF document text
    • https://tranhdaquyhn.com/uploads/news_file/17090374930.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/1accdfcd9b92b49efc0b1e72a6cb0b96/64867757824.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/6fb8a7081a7dd02c7085f2e12a4dd4dc/68367330502.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161345eed24036---16483493762.pdfIn PDF document text
    • http://groupkaishan.com/d/files/vatuvipugugolabebuvusix.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/21080726022.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/tipipotonesidob.pdfIn PDF document text
    • http://www.sandipmallick.com/fckimages/file/70010574759.pdfIn PDF document text
    • https://vaitinhdien.com/app/webroot/upload/files/28217398761.pdfIn PDF document text
    • http://17njl.com/userfiles/files/jalotowazozivapogefinobi.pdfIn PDF document text
    • http://riviera.az/userfiles/file/xofuk.pdfIn PDF document text
    • http://geriatriccarenewjersey.com/userfiles/files/xaliz.pdfIn PDF document text
    • http://elisa5888.com/shopadmin/upload/files/kodudupeselirim.pdfIn PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/refiropesovadupitotalo.pdfIn PDF document text
    • http://sage-chem.com/image/files/20210902_223733.pdfIn PDF document text
    • https://hfbee.tw/upload/ckfinder_temp/files/20210916051420.pdfIn PDF document text
    • https://ventadeterrenosurbanos.com/userfiles/file/fobetenawix.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16136a8a891f23---59908213781.pdfIn PDF document text
    • https://tierrettung-in-katalonien.org/ckfinder/userfiles/files/wafabebeluwovad.pdfIn PDF document text
    • http://penetrat.ru/files/files/vajivosagab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=marvel+future+revolution+iosPDF 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_off0000de82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE82 17360 bytes
SHA-256: ac9ab12104099e9fe2c53b26a911641669b7948f79b6024ad0b62633a4a4a57c
font_01_sfnt_off00010b2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2C 10364 bytes
SHA-256: f02ee270430e87fa687362d25d3f4b35d6bce5598dde7889f18285e68411150f
font_02_sfnt_off000122bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1