Malicious PDF — malware analysis report

Static analysis result for SHA-256 a255bf16b9a46fe9…

MALICIOUS

PDF

69.6 KB Created: 2021-09-18 07:34:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 64e883d11f2bb4b9d6deee78a5875f74 SHA-1: e68d2136ca966534c61e4bbe587dbe0e468a41b2 SHA-256: a255bf16b9a46fe946ffaeeca6f73680cc6f08fe52b8ef976972781a30d5fb00
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic confirms the presence of a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • 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 http://parkergeneralcontractors.net/userfiles/file/95035158055.pdf In PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/lumisabififad.pdfIn PDF document text
    • http://klawiatury-foliowe.pl/_data/file/73710802409.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/tafepamowirugubibivomo.pdfIn PDF document text
    • http://littlepearlbooks.in/data/eimages/file/nilirozexitikim.pdfIn PDF document text
    • https://futurefacesmiami.com/uploads/file/63306966518.pdfIn PDF document text
    • http://world-green-hope.com/uploads/files/sadidi.pdfIn PDF document text
    • https://boucherienabli.com/uploads/FCK_files/file/nexofuwofizi.pdfIn PDF document text
    • https://manorhair.com/uploads/files/202109140209447961.pdfIn PDF document text
    • http://cpviettin.com/upload/files/fapizubezomiwelok.pdfIn PDF document text
    • http://www.civilhospitalpalampur.in/img/uploads/files/21958629252.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613d8f0c24fc5---67901888222.pdfIn PDF document text
    • http://zwickerfoto.hu/_user/file/fozalugipijigim.pdfIn PDF document text
    • http://lotusburbank.com/uploads/files/vexadosoviledudif.pdfIn PDF document text
    • https://alternatifhirdavat.com/upload/ckfinder/files/82528837981.pdfIn PDF document text
    • http://longvu.vn/Images_upload/files/vawuxezuvovalulobefipelex.pdfIn PDF document text
    • https://ratsimae.ee/media/contents/file/vufironifaburebotumiba.pdfIn PDF document text
    • http://phamtrangia.site/upload/files/levilofegojupewoziv.pdfIn PDF document text
    • https://ribaczpeter.hu/files/file/64744514060.pdfIn PDF document text
    • http://mfo-fond.ru/ckeditor/ckfinder/userfiles/Images/files/998462103.pdfIn PDF document text
    • https://batikatravels.com/userfiles/file/kezobefox.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/82149910923.pdfIn PDF document text
    • http://quimis.net/js/ckfinder/userfiles/files/zowugadazeruruzupitiz.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/45160903236.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=create+keystore+flutterPDF 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_off0000b16f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB16F 10348 bytes
SHA-256: 5b1baf96b62f353eb6364c321651acb2ae6976ea61d83538424009b6c9b01675
font_01_sfnt_off0000c913.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC913 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e125.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE125 15740 bytes
SHA-256: 78ef14f526c2a4c9a2452702102e9ae89218c2d6050760b5c5b0f3cbefebac8d