Malicious PDF — malware analysis report

Static analysis result for SHA-256 c610d2eec75bbd0d…

MALICIOUS

PDF

72.9 KB Created: 2021-09-25 12:51:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b08290ae0738baec8bca48952f8f31b1 SHA-1: 87e0f3b48b631d00dbbccda72264f270a7a7d382 SHA-256: c610d2eec75bbd0d3cb9ab5dfcc1a1dd128ad8efe7574b50485ab45d82feca76
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://infrive.ru/uplcv?utm_term=apk+runner+for+pc PDF link annotation
    • https://somogyplusz.hu/files/mudosizisomizomekisiz.pdfIn PDF document text
    • https://khonggiansachhanoi.vn/uploads/files/12516275792.pdfIn PDF document text
    • http://noithatmyhome.com/img/files/52124241578.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/161425ca920885---kenotudos.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16145716f18073---pibovawe.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c6fc34ec9c---3797315037.pdfIn PDF document text
    • http://cuacuonnhanh.vn/Images_upload/files/72744249310.pdfIn PDF document text
    • http://www.sudeshnamaulik.com/fckimages/file/vapalu.pdfIn PDF document text
    • https://copacndg.com/images/uploads/files/21038954521.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/2894000172.pdfIn PDF document text
    • https://teamcode.net/upload/files/lujexuk.pdfIn PDF document text
    • http://dichvugiayphep.biz/upload/ck/files/xapabukotuvimo.pdfIn PDF document text
    • https://rheinfurth.de/userfiles/file/75439108105.pdfIn PDF document text
    • http://cheapmarkt.com/userfiles/file/92587514971.pdfIn PDF document text
    • http://slenderclub.cz/ckfinder/userfiles/files/poseximugapufitoxuwo.pdfIn PDF document text
    • http://satcomlink.com/userData/board/file/39263001159.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614a081dcf4c0---51395206047.pdfIn PDF document text
    • http://asia-test.informacittadino.net/media/files/nedodak.pdfIn PDF document text
    • http://neogmbh.de/www/sites/default/files/userfiles/file/rokavapebawexabajisesozo.pdfIn PDF document text
    • http://binhthuocsau.com/hinhanh/file/ruvatumolidagide.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1614e34d7b46cb---2513167190.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614b4c310f4c3---wugidobevidi.pdfIn PDF document text
    • http://phongthuydotho.vn/upload/files/xowogelotigonepewusosi.pdfIn PDF document text
    • http://kingtonkatsu.com/uploads/files/8708557451.pdfIn PDF document text
    • http://xn--80aap0abfiql8h.xn--p1ai/admin/ckfinder/userfiles/files/16640482327.pdfIn PDF document text
    • http://mazurubezpieczenia.pl/zdjecia/fck/file/xokiko.pdfIn PDF document text
    • http://kondicionery-elektrostal.ru/upload_picture/file/38117813796.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_off0000b71b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB71B 10080 bytes
SHA-256: 8bbf0217243da55193b784f570881a0c558a962a53ec231df8ecd7bf2153b78e
font_01_sfnt_off0000cdb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e5ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5CA 18740 bytes
SHA-256: 947b8e3fbf0e0f0c6076d71826eed85e4ca6d1c8ca7b1031d6ce1cf7a6e752ea