Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffff873bf06d30e1…

MALICIOUS

PDF

101.8 KB Created: 2021-09-05 18:48:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b5ccef1b6c0b67d392537ee97a2d3c88 SHA-1: ddddfa87b6df5b217ea0b8af5a18df73cdb4fca8 SHA-256: ffff873bf06d30e19224c578c9dfbc93ddc57d337283987b996d5ca69d7378ee
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 CMS upload directories, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://facades-metal.ch/ckfinder/userfiles/files/fenerosapalapamorubo.pdf In PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/33272014888.pdfIn PDF document text
    • http://www.abcklima.hu//data/editorfile/suzuraratefiwupeseludevu.pdfIn PDF document text
    • http://blueleaves.ru/userfiles/file/58635446201.pdfIn PDF document text
    • http://sgrappresentanze.eu/userfiles/files/kifeb.pdfIn PDF document text
    • http://thrifty-uy.com/files/others/74421841171.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///21124313647.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/domaxijus.pdfIn PDF document text
    • http://cn-junsheng.com/upload/file///2021626172899634.pdfIn PDF document text
    • http://www.lnk-creation.fr/upload/file/20857053850.pdfIn PDF document text
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/jigakosopovusewume.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/9e6a59a2bc50d10fcecde2c809bdeac1/3951573549.pdfIn PDF document text
    • http://elpijisystem.com/file/95720527450.pdfIn PDF document text
    • http://gurukripapublicschool.com/userfiles/file/jifomupujagulupodamino.pdfIn PDF document text
    • http://travisreunion.com/clients/1/1d/1d9c560ef9ee6310b862f4c9d288d7bd/File/sobimuwazenugeduz.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/kiwadot.pdfIn PDF document text
    • https://gruntbudowa.pl/files/file/jakumegonosefizofe.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611706500dd38---towedixemugulipizezo.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/9a24d84d80ab6d96b23fdc9a234336cd/rutosabawata.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/161084358ba9ed---9364057642.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16076833ef2cc5---xogurexuxi.pdfIn PDF document text
    • https://jf-orvalho.pt/userfiles/file/zimovetojugusukojazumizon.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/58267354647.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=dungeons+and+dragons+rules+cyclopedia+pdf+downloadPDF link annotation
    • http://crossfit28.com.s125853.gridserver.com/siteuploads/editorimg/file/37320747330.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_off00011904.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11904 22732 bytes
SHA-256: 0069a028013bb76d53ca77dc71aa71d544fc487b138144ead105adbbdeb96dbc
font_01_sfnt_off00015575.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15575 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016d8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D8C 10996 bytes
SHA-256: c2c26d5025ee5fa08cd72bfc29d7866af20c21a238a79084d6a447b260d42075