Malicious PDF — malware analysis report

Static analysis result for SHA-256 813773bf3fa8d4b8…

MALICIOUS

PDF

69.7 KB Created: 2021-10-03 05:27:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3f7633d2e3c7a012e91c04d7821ad2f5 SHA-1: 2feb3e82bd1dfc9642a43cb000c63d20b0115300 SHA-256: 813773bf3fa8d4b87496aa5456564b2460917556064388b5173a58aa6301f678
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various websites, many of which are hosted on compromised CMS platforms or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through these links. No scripts were extracted, but the structure suggests a link farm designed to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://wastran.ru/uplcv?utm_term=universal+healthcare+single+payer PDF link annotation
    • http://kleinschaden-expert.com/userfiles/file/pofadetukidibuduxos.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/19363248281.pdfIn PDF document text
    • https://eledigitalpr.it/allegati/file/valutugevesunamorisido.pdfIn PDF document text
    • http://sanga.asia/userData/board/file/xenagosiwozexofifaduki.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/161590cc4d693e---keruz.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/27167807462.pdfIn PDF document text
    • https://wintechindia.in/ckfinder/userfiles/files/rubizixijotagim.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/51994775256.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/43429961383.pdfIn PDF document text
    • https://trade.inter-ural.ru/ckfinder/userfiles/files/renifanuxarul.pdfIn PDF document text
    • http://agenziaimmobiliarecannavo.eu/userfiles/files/95829123568.pdfIn PDF document text
    • http://apcmagon.com/userfiles/94441957892.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614280f5276b4---14480579898.pdfIn PDF document text
    • http://sakesushilakehavasu.com/uploads/files/51979163958.pdfIn PDF document text
    • http://budgettranslation.hu/sites/default/files/file/serexe.pdfIn PDF document text
    • http://glampingcaravan.com/userfiles/file/20210921195001.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/lso1lahkb5d59bkc0jp3mumlo6/tozosujew.pdfIn PDF document text
    • http://www.iciparis.ru/ckfinder/userfiles/files/8240487731.pdfIn PDF document text
    • http://upservice.expert/admin/ckfinder/userfiles/files/betozoresikedafeveg.pdfIn PDF document text
    • http://myblindz.com/fck_user_files/file/manolibuvuwalivimuwaxoj.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615718f2b4e8c---nogekamuki.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/mewowom.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_off0000af19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF19 10720 bytes
SHA-256: 6ee6d2588975a6deb75757a349e9582513d90fe811f669f05acd426902563e13
font_01_sfnt_off0000c7b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7B6 16420 bytes
SHA-256: ef4ec6980115103bd88bca8b790c4a2282aadb3e86fab84ab911bedd0bdf1b19
font_02_sfnt_off0000f1a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1