Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5c557a428495c6e…

MALICIOUS

PDF

83.0 KB Created: 2021-09-16 22:02:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d137ddda20099b4c1f633a94af41e11a SHA-1: 88316ca4fa7a770f7ccac3724ae136c300b68c96 SHA-256: f5c557a428495c6e0fa9bc76b57818d15e311a290cf0bb481d8cadec311d7f88
134 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier with high confidence. It contains numerous embedded URLs pointing to potentially malicious PDF files, suggesting a link farm or downloader infrastructure. The presence of a 'Download Now' heuristic further supports the intent to trick users into downloading a malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/3d3226bc778a35ba3fdf5c8d2b06f8a0/minupiliwinixi.pdf In PDF document text
    • http://roomyab.ir/basefile/roomyabir/files/50177915207.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/17574993403.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/kedujerizixegexozeta.pdfIn PDF document text
    • http://vasekurzy.cz/userfiles/file/10328182767.pdfIn PDF document text
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/kakukokuvikunuropijimoje.pdfIn PDF document text
    • http://uforoi.com/app/webroot/uploads/files/jakufutopirog.pdfIn PDF document text
    • https://www.habitat-morvan.fr/ckfinder/userfiles/files/sagatotizefiwaxoxudogim.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161321eeb2e09b---2164383421.pdfIn PDF document text
    • http://ourgans.org/userfiles/files/32918814546.pdfIn PDF document text
    • http://shopgraeagle.com/ckeditor/uploads/files/kajediwebinipafobog.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/66892898493.pdfIn PDF document text
    • https://szabolcsipeter.com/userfiles/file/61176546161.pdfIn PDF document text
    • https://cdmsig.com/ckfinder/userfiles/files/tojebibafonivop.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1631305197.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/darewamijopagabudivew.pdfIn PDF document text
    • http://www.village-gaulois.org/gestion/ckfinder/userfiles/files/20835558666.pdfIn PDF document text
    • http://6nergy.fr/6nergy/sites/default/user/file/vugejidetatir.pdfIn PDF document text
    • http://kimhoatra.vn/upload/fckimagesfile/gurorokeben.pdfIn PDF document text
    • https://myreply.mobi/snappshott/editor//file/9320040046.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/37339586993.pdfIn PDF document text
    • https://tssch.in/tssch/application/admin/uploads/file/42179740234.pdfIn PDF document text
    • http://monikaknoblochova.com/userfiles/file/68952870616.pdfIn PDF document text
    • http://belniig.by/public/file/jefukelixakeg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=adm+app+apkPDF link annotation
    • 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_off0000dbb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3CF 9768 bytes
SHA-256: 8e497f5d6c2a054b00423d7cf2629a0aa4c013e735e5852c8092b1a87df02e50
font_02_sfnt_off00010920.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10920 20344 bytes
SHA-256: fef23979c0fb487d8096ba4039d0b1b97a8d813a5b3e184cad5b6c99629f3d05