Malicious PDF — malware analysis report

Static analysis result for SHA-256 add508d1fc26f878…

MALICIOUS

PDF

69.5 KB Created: 2021-09-14 14:07:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2fd353ba3ba792fdd8ea27675f4984f9 SHA-1: 103b3c8a0745a64db64e7eba2ffc5a5ba8dd07c3 SHA-256: add508d1fc26f8780517031f62c1a531af38166b862620c2fc66c63d9b016e21
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to potentially compromised websites or disposable hosting, indicative of a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://crysiq.ru/uplcv?utm_term=simple+words+that+start+with+l PDF link annotation
    • http://doingthing.com/downloads/blog/geust/files/88650728593.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/55696750574.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/37667881695.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/48194932688.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613cde9235a90---1937621359.pdfIn PDF document text
    • http://qianxish.com/ckfind_image/files/sewede.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/luzogijaw.pdfIn PDF document text
    • http://solarissoft.com/img/userfiles/files/79697975571.pdfIn PDF document text
    • http://ressourcengarten.de/azubi/userfiles/files/59700510547.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d9a2fcbc3c---nemamoroz.pdfIn PDF document text
    • http://wonderful-foods.net/userfiles/file/16696649069.pdfIn PDF document text
    • http://alfavs.eu/userfiles/file/14325068715.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/fotipajoselolezomomopa.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/tivok.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/9a870ce629b73dd9098b721769b6ff5f/wabibojizobupuziwufil.pdfIn PDF document text
    • http://seanbittinger.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tewujupopu.pdfIn PDF document text
    • http://dohertylaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/8238086181.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/6212877034.pdfIn PDF document text
    • https://greenlakepaint.com/ckfinder/userfiles/files/15636348200.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/421d04d7c1a09df23e58ada648488e4c/43823311289.pdfIn PDF document text
    • https://llbyggodesign.se/UserFiles/files/38493033.pdfIn PDF document text
    • http://apvn.info/userfiles/file/zulusakenusivajosulenawoz.pdfIn PDF document text
    • http://lesbambousbleus.fr/ckeditor/upload/files/jijotitazutejes.pdfIn PDF document text
    • https://afayl.com/userfiles/file/20822671140.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_off0000b138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB138 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c94a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC94A 15344 bytes
SHA-256: 475f84325e393971449930572d46187714bd578832813953ea23ba8b39603aa0
font_02_sfnt_off0000f02c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF02C 10716 bytes
SHA-256: 7253c85dc2d83dfd2d45285147e75cdd72a4017e58bcbc76451fe59505b3862c