Malicious PDF — malware analysis report

Static analysis result for SHA-256 44a10534642867e2…

MALICIOUS

PDF

86.4 KB Created: 2021-06-29 11:57:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 7b9d770ae4849aeaa6f06920ec3a9904 SHA-1: dff9d123de964a00fc31f2a4dae3fd1366359997 SHA-256: 44a10534642867e291d174c377debce8094478d44365e47ccaca645d7a9d3106
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains a link farm pointing to numerous compromised WordPress upload directories and disposable hosting sites, suggesting an attempt to distribute malicious content or phish users. The presence of external URIs and a link farm heuristic strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9765

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://feng-shuiworld.com/userfiles/file/70864164030.pdf In PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210625_152227.pdfIn PDF document text
    • https://bwawarszawa.pl/upload/file/tabigibubogosumebenavuru.pdfIn PDF document text
    • https://oliogalanis.com/file/guzaso.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/89730303122.pdfIn PDF document text
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/qs85htakgm1nfvs33etf7rmake/pupadevevidi.pdfIn PDF document text
    • http://srividyaastrology.com/userfiles/file/37912176495.pdfIn PDF document text
    • https://southwestlooms.com/admin/userfiles/files/xotimigimejori.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/d1bf0019c082d04e670ba0519732b4ae/bakufesap.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/c850b4d59be864be1e7b171ac9de63cd/74919102849.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a7dce245b---titodoma.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160843fb82dc30---26762968730.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b361ed73a12---bekixelelaninupumojinogub.pdfIn PDF document text
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/e666809cf77b5c00f05c2369e4545aeb/76947956890.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608035ad212b9---33976548960.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160ca0488bbf5a---63843316725.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/d9f8983b23bd3a5ce440914d8cdf5bdb/rujewedabisonuzoneve.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/t4qovjbs7kapqb0fcvmq5l3bhb/pakukumepamisase.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/63690672189.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/9ec7127dcd674fe1523e4ebacf8d305a/debozuwirekujizisu.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/gufezupigobaboxexiwil.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/titabamofe.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/72751736291.pdfIn PDF document text
    • http://blackivy.pl/userfiles/file/tavus.pdfIn PDF document text
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/17284803a7968669f037e36870a7615d/nogukarolunepaxugato.pdfIn PDF document text
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/pbbf3kb3fj24clal0egskqfbcr/xajopujitevufirolabetugo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=michael+bolton+lean+on+me+song+downloadPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d48e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48E 17960 bytes
SHA-256: 8a989e51d06030a1bd5c3f92bb4786ac9d511fda5240815db3567412ad4e8a25
font_01_sfnt_off000103d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011be5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BE5 16340 bytes
SHA-256: 5ca0f057fbf63f5682e7944538b20cd34cad7b03a9ae8dd6a9e175cb923574e4
font_03_sfnt_off00013250.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13250 10936 bytes
SHA-256: 7c0904b24d75ae75dbc67686054218c3dfa484df26fb8ee329b4a7617a3c32b6