Malicious PDF — malware analysis report

Static analysis result for SHA-256 f79b2f93953f2809…

MALICIOUS

PDF

94.6 KB Created: 2021-08-14 04:15:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 04626ee3fbf8b767ecac3a55cd1db214 SHA-1: bbe9132e6342f8a0a60b4f4ecb82b8c7e182504f SHA-256: f79b2f93953f2809c8ee09e81da85e505218d060ac081a939d84a190a894a8db
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The presence of compromised CMS upload links suggests an attempt to host malicious content on seemingly legitimate but compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 http://northcity.rs/slike/files/gavez.pdf
    • https://vibangthuaphatlai.net/uploads/files/sudumipasujizil.pdf
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/a2f2dcab684c2ac3164b5dec416b5734/kerulafigibidimib.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098e80057f41---77220093166.pdf
    • http://aldobini.it/userfiles/files/81385804490.pdf
    • http://gwardiajuvenia.pl/zdjecia/fck/file/39162191709.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/hfsnk11i4cq4he0e8ak4cnmsk9/nimigujatajosotesurimeniw.pdf
    • http://mckeoughfamilyreunion2021.com/clients/b/ba/baf9e6b347377fae0abe5a87436fc4cf/File/kuwuwubixid.pdf
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a87f9fb47e7---57194829352.pdf
    • https://alamansyria.com/userfiles/file/tofomabufoki.pdf
    • https://dom4m.de/userfiles/files/lanez.pdf
    • http://fiumaradelsossio.it/userfiles/files/57500561015.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089022c3d93b---7571558165.pdf
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/39163807245.pdf
    • http://brianhaymore.com/images/e/file/zozekazokorigobaxox.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a38e3920318---27860676505.pdf
    • http://maszyny.pl/userfiles/file/47516799938.pdf
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/jemolegudobozivipepixeru.pdf
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kuwavepitogizubobe.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092a741c605c---kuporinajubozuvolupafav.pdf
    • http://resetimpianti.it/reset/public/file/82187558025.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=livro+v%C3%A1+cuidar+da+sua+vida+pablo+mar%C3%A7al+pdf+gratis
    • https://www.unimedbelem.com.br/painel_template/assets/global/plugins/ckfinder/userfilesfiles/72563107009.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001055a.bin
bef8f0c65a80cc919b847f9d99bdbd6fe63268cf15652a8dda15760a01cc7fa8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1055A 11368 bytes
font_01_sfnt_off00011f10.bin
5dedd01c0943a825b05c0fcee447fc06b794ab97d9c2ba6879181c65e6a04c71
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F10 20120 bytes
font_02_sfnt_off00015067.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15067 16792 bytes