Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f028fe9b1338331…

MALICIOUS

PDF

71.0 KB Created: 2021-09-27 06:06:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0a2f1e0283697348fe00c971206d9d95 SHA-1: 1a0a58f4d580e92212d3f9f8963ea9d4c728673b SHA-256: 4f028fe9b133833103395b068efcd617ebf828fc4025f01bbdc3884858edb7a8
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads or disposable domains. The presence of numerous unknown-reputation URLs suggests an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://medvor.ru/uplcv?utm_term=tales+from+the+yawning+portal+5e+pdf PDF link annotation
    • http://maremania.net/img_pagine/file/88727021552.pdfIn PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/66518556873.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16143f4eb92494---bivifujax.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/gasubigefumumegiv.pdfIn PDF document text
    • https://easresidence.ro/app/webroot/files/userfiles/files/jotujizavijafat.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/6ouhoakhid40bbq3m2v030m5j6/fodon.pdfIn PDF document text
    • http://kientrucsangtrong.com/plus/files/95255348819.pdfIn PDF document text
    • https://saglamahsapkutu.com/img/editor/image/file/nudemiref.pdfIn PDF document text
    • https://enerjimakine.com/tsrm1/img/userfiles/file/97255371056.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/47324227611.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/37507715800.pdfIn PDF document text
    • http://hstairan.com/FCKeditor/editor/filemanager/connectors/php/userfiles/file/bemaferetut.pdfIn PDF document text
    • http://telek-trans.hu/editor_up/xavolajevakomolizivogu.pdfIn PDF document text
    • http://ejmk.com/ej/upload/files/zefigurumafe.pdfIn PDF document text
    • http://fullx.net/files/mikovuf.pdfIn PDF document text
    • https://synodradomski.pl/userfiles/file/kefuzur.pdfIn PDF document text
    • http://letsbelegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tusedozeloj.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/8duom26q9cc7b3ncipmajssi9h/20707356704.pdfIn PDF document text
    • https://varida-tech.com/ckfinder/userfiles/files/bozokosilidapi.pdfIn PDF document text
    • http://areawifi.com/DESARROLLO/userfiles/files/tewutasojix.pdfIn PDF document text
    • http://nagymester.com/userfiles/file/sukelawukas.pdfIn PDF document text
    • http://studioaba.net/userfiles/files/64053170412.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/71428664037.pdfIn 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://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_off0000afb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB8 17352 bytes
SHA-256: 2e4cd491db8439c044bd9bc1a2b1d735ed33d1b0c96684a376200ead2dded557
font_01_sfnt_off0000dc72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC72 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f489.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF489 11240 bytes
SHA-256: afb870dceb6cc8a408e78b9b991c5221f374dca510826ee64eb39a71ef9b9ce4