Malicious PDF — malware analysis report

Static analysis result for SHA-256 a24f4421ceb2eee9…

MALICIOUS

PDF

85.5 KB Created: 2021-10-06 21:02:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: a3e10f5d74be043a1269114e5c15574f SHA-1: 041cd4f4c713dcf5527fd384d3df3f44081f3091 SHA-256: a24f4421ceb2eee969e7588f20a5be6b5d21d4e78925f84a340d397bc197b6fd
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://chcial.ru/uplcv?utm_term=discord+chat+markdown PDF link annotation
    • http://avandcie-energy.fr/ckfinder/userfiles/files/42321664956.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/68764774887.pdfIn PDF document text
    • http://inimtrento.it/userfiles/files/85844597077.pdfIn PDF document text
    • https://mtestbd.com/assets/uploads/files/15594091805.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/gelaxasezefejus.pdfIn PDF document text
    • http://addisonplaza.abwingsmd.com/uploads/files/99037669006.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615258d37d65d---2475496944.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/durakajinexomijulajumu.pdfIn PDF document text
    • http://avtrak.ru/ckfinder/userfiles/files/pisoropabovit.pdfIn PDF document text
    • http://engineersclasses4competition.com/files/others/68334621357.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/benujotugojep.pdfIn PDF document text
    • http://romanasulcikova.cz/userfiles/zozavugawagofobegata.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/82834016568.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/4412f485291e68091ecd4351c6116b15/39281331508.pdfIn PDF document text
    • http://jcpingie.be/public/files/peduvefuraj.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/memomatebabijanunetilitol.pdfIn PDF document text
    • http://santeh.md/img/files/vewigusupanuzav.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/9a8f4e3b008e25bd4d81176682b983ea/47302396535.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/14d2a2f1b5bef37932f63fe99f818bbb/2476314176.pdfIn PDF document text
    • http://salman-group.com/userfiles/file/52575134503.pdfIn PDF document text
    • https://nbc.com.vn/ckfinder/userfiles/files/15393837525.pdfIn PDF document text
    • http://buzmakov-ua.ru/admin/ckfinder/userfiles/files/14427891933.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_off0000e477.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE477 18996 bytes
SHA-256: 447b648d8acb098a528f5c0866ef38fc9bffcfd2fd753f4246db2c44c19d5b98
font_01_sfnt_off00011713.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11713 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012f2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F2A 10636 bytes
SHA-256: 2a9f6279eba602a44308dbc36ad270a629952414d98fb626782197c1ca4dadbb