Malicious PDF — malware analysis report

Static analysis result for SHA-256 181b7cf8645e1ca7…

MALICIOUS

PDF

82.0 KB Created: 2021-09-18 15:47:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 792c45f2dd5d218d5bda8a4d1ff9fc6a SHA-1: 7bfb0d50e03f5b6798aec03a19fbe83384e4c412 SHA-256: 181b7cf8645e1ca7df04e493911ff898ba371ca1a38a9fbc3cafd0652d20c9a7
204 Risk Score

Malware Insights

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

This PDF contains embedded JavaScript and multiple links to external PDF files hosted on compromised websites, indicating a phishing or malware distribution attempt. The 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggests the document is designed to trick the user into installing malicious software disguised as a browser update or extension. The ML classifier and ClamAV detection further confirm its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16134e7879e3a2---vesenoralowapot.pdf In PDF document text
    • http://celeb.huh.hu/UserFiles/File/levimob.pdfIn PDF document text
    • http://soleilboo.com/images/uploads/files/82652526026.pdfIn PDF document text
    • http://www.hussco-steel.com/husscofiles/files/puvewavo.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/09209e028f0bd84ffb9ddbb49fdb155c/93763844262.pdfIn PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/26650094231.pdfIn PDF document text
    • https://senfina.top/uploads/files/56186261201.pdfIn PDF document text
    • http://plise.org/userfiles/file/70336872375.pdfIn PDF document text
    • http://autoset66.ru/admin/ckfinder/userfiles/files/61648771001.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/f6cce821cd9e187e95ae03a87b1c52c6/turorejalibixabekil.pdfIn PDF document text
    • https://yaofangpeixun.com/upload/files/35153605148.pdfIn PDF document text
    • https://e-midas.ro/files/file/favezufalixesovew.pdfIn PDF document text
    • http://eluvial.com/sites/all/sites/eluvial.com/files/zigasozusajogeniduna.pdfIn PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/4587082e906ebda060085b04ef7e96c7/60562408064.pdfIn PDF document text
    • https://volandovia.it/public/fileeditor/file/pakijadokexivilizazaso.pdfIn PDF document text
    • https://cebrigantina.com/025-CEB/images-editor/file/97563508865.pdfIn PDF document text
    • https://vongtaytramhuong.vn/upload/files/pokusela.pdfIn PDF document text
    • https://drproperty.in/userfiles/file/74384696206.pdfIn PDF document text
    • http://dunajecbiala.pl/upload/File/jiparaluleninidutiv.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/senejuwulawedezupu.pdfIn PDF document text
    • https://arbormaster.net/uploads/files/gowosojuwufofiw.pdfIn PDF document text
    • http://technoauto.jp/js/upload/files/60640279819.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/58182479148.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=empire+season+6+online+freePDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB81 18136 bytes
SHA-256: 27f0e6f216a76ee200a6589172baca170867c6db17e1aab3971552b3b86b004c
font_01_sfnt_off00010a53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001226a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1226A 10572 bytes
SHA-256: 3b398357511e14986243e6e642a4eb34138536f18734980af1836fb7c0fb3c75