Malicious PDF — malware analysis report

Static analysis result for SHA-256 84d6e4a2591efcf0…

MALICIOUS

PDF

68.8 KB Created: 2021-09-27 10:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b2745a3b658466c387e83a6c78b24424 SHA-1: 0671e1748b2bd238793b8e4dd06b7ebb684be1b0 SHA-256: 84d6e4a2591efcf071cd38d57488937d278c2cba523c496489198b6567b64328
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm for SEO manipulation or malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://medvor.ru/uplcv?utm_term=how+to+use+android+phone+as+graphic+tablet PDF link annotation
    • https://indiantiffin4me.com/nbloom/fckuploads/file/62884212725.pdfIn PDF document text
    • http://taketty.xyz/js/ckfinder/userfiles/files/rufonerowifolupadukixum.pdfIn PDF document text
    • https://apagar.cinemadossertoes.com/ckfinder/files/37596820865.pdfIn PDF document text
    • http://ez-surveying.com/htdocs/cljr/data/files/radadixi.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/jowibifijujazelax.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/93721206782.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/gexijiwevixevirojumiwilok.pdfIn PDF document text
    • http://104408017.linker.tw/files/25601194796.pdfIn PDF document text
    • http://scro.ru/pic/file/53062885740.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d680f461fc---datojutafidexilalokomon.pdfIn PDF document text
    • http://fitviewer.de/files/file/31842989399.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/47629368807.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/9c98adac69a7c12c140a1294e731a202/11324753811.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614a28fc6a487---89616126756.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/kemugusovarapodi.pdfIn PDF document text
    • http://darec.sk/files/files/figufuwukulodibironabu.pdfIn PDF document text
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/fulafurojisegudebakelavuf.pdfIn PDF document text
    • http://www.slenderclub.cz/ckfinder/userfiles/files/84931022980.pdfIn PDF document text
    • https://esofagopisa.it/userfiles/file/bixoso.pdfIn PDF document text
    • http://drthchowdary.net/userfiles/file/zakinavozewubotipas.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_off0000aba9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xABA9 16068 bytes
SHA-256: 637112f81eeb6881ddfb35cf902fd7d65c547014573bf2f8b3f8c436d94dc3d1
font_01_sfnt_off0000d489.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD489 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eca0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA0 11112 bytes
SHA-256: 2544bcb00cafe2a924d74ceec5bafefdd351a29a61580bef7fe99bc111e073a3