Malicious PDF — malware analysis report

Static analysis result for SHA-256 f88448aaebca4f40…

MALICIOUS

PDF

83.2 KB Created: 2021-09-24 08:06:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7ae03ebfdbdc52bcce09eca6c02cf640 SHA-1: d36499e14e80c92dbfc76eb5bca88c758a246353 SHA-256: f88448aaebca4f40ef2db6dc3b85cbdaec8e185bf040afa15541ea37a3874032
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to disposable domains, indicative of a link farm designed to redirect users to malicious content. ClamAV detection and ML classification strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and numerous external links are consistent with a spearphishing attachment used to deliver a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://cructi.ru/uplcv?utm_term=play+minecraft+online+free+new+version PDF link annotation
    • http://zentrumok.com/userfile/files/gevuduxokililobo.pdfIn PDF document text
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/12708882148.pdfIn PDF document text
    • https://rugsinc.in/UserFiles/files/borezupevakuro.pdfIn PDF document text
    • http://captaincook.hu/userfiles/file/28553295364.pdfIn PDF document text
    • http://circuitoinsulargc.com/documentos/file/pofoxugemiwusororomopu.pdfIn PDF document text
    • http://sov.tranovice.org/webpagebuilder/ckfinder/userfiles/files/90682644540.pdfIn PDF document text
    • https://nirkongrp.com/ckfinder/userfiles/files/66395643570.pdfIn PDF document text
    • https://servingltda.com/userfiles/file/94405491318.pdfIn PDF document text
    • http://smartickgroup.com/userfiles/32291392867.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/kivulapenigejon.pdfIn PDF document text
    • http://beiwendq.com/data/attachment/file/26680642092.pdfIn PDF document text
    • http://colegiosantarosa.com/uploads/imagem/file/sululojeburuvinizivix.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/limer.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/a2b858b2dbgf7i8d4668t6239j/28753320323.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/78ser7tt1n4a5n9a0eupkdt0h7/vafupurusuzoge.pdfIn PDF document text
    • https://support-trevianum.nl/userfiles/files/gusiwebilumesoxis.pdfIn PDF document text
    • http://bayanairag.com/uploads/userfiles/files/26940449812.pdfIn PDF document text
    • https://kvizek.hu/ckfinder/userfiles/files/54239167982.pdfIn PDF document text
    • http://vinhthuanvietnam.com/upload/files/dotefuvi.pdfIn PDF document text
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/90077465687.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///mojiganomoradego.pdfIn PDF document text
    • http://traiteurluc.com/userfiles/file/demixudud.pdfIn PDF document text
    • http://futuralagoparking.eu/userfiles/files/povirimav.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/71747237268.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_off0000e1fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA0E 17028 bytes
SHA-256: db63e7fe5ed6f8a16073459fbdb6193bd435a6fb1729718aac743554bcab00a2
font_02_sfnt_off000125fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125FC 10764 bytes
SHA-256: a268c6a0e9e07df95a95030f40a252ec234ede463b247befc4422cdc35c0f59f