Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c7ecd3736fd52fd…

MALICIOUS

PDF

74.7 KB Created: 2021-09-09 11:33:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 21b10be22930ac82cb0bc25821702177 SHA-1: f5193b23ecc67ad92b0c6e3e8a3c1b03cff813a5 SHA-256: 4c7ecd3736fd52fddab1778b102c8bacddb4a70ce0966566899ae05d1bcf3173
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The presence of numerous URLs, including one with a 'utm_term' parameter suggesting tracking, reinforces the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://ketchas.ru/uplcv?utm_term=moto+x3m+bike+race+game+to+play PDF link annotation
    • http://muasamhangmy.com/ckfinder/userfiles/files/65557968997.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/xiwasisosunitezejuz.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/161305cf41c49a---sirapigudoze.pdfIn PDF document text
    • http://www.jfac.kr/ckfinder/userfiles/files/kivupesakulav.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/virinozoxes.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/86492937430.pdfIn PDF document text
    • http://tjjjsh.com/uploads/files/47391693203.pdfIn PDF document text
    • http://www.ettermanenterprises.com/ckfinder/userfiles/files/79523095771.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-09-06/images/files/fekebinimibekov.pdfIn PDF document text
    • http://yanartextil.com/firma/files/fikinibada.pdfIn PDF document text
    • http://flirtproducties.nl/ckfinder/userfiles/files/nafazifuxisep.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303c447173a---pululafedosawewukomov.pdfIn PDF document text
    • http://sushiosushi.com/uploads/files/turufelanufewenirozaw.pdfIn PDF document text
    • https://asesoriagade.com/app/webroot/files/files/2712580832.pdfIn PDF document text
    • https://client-sms.com/ckfinder/userfiles/files/regozokifebonomabepabixo.pdfIn PDF document text
    • http://brno-skoleni.cz/ckfinder/userfiles/files/kinegamabivadejate.pdfIn PDF document text
    • http://lionsmarsala.it/userfiles/files/67936311996.pdfIn PDF document text
    • http://kammed.com/userfiles/file/medamovogurumujobufidu.pdfIn PDF document text
    • http://citysoupsbellevue.com/uploads/files/kipezafixebama.pdfIn PDF document text
    • https://beldapin.com/calisma2/files/uploads/nifosula.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135bd8e4d6bd---5270966960.pdfIn PDF document text
    • http://thienthaopc.com/upload/FCK/file/91208123443.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_off0000c1f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1F8 16028 bytes
SHA-256: 260332fb82e3a8f3bbad4d411f357a8e6c4d18ab2bb71218e0f2ec3f795b0acb
font_01_sfnt_off0000eb24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB24 11056 bytes
SHA-256: a215abeea72d34f884e80a622152e182adcead8754b90aabf210795e38e3b737
font_02_sfnt_off000104ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1