Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b4c4f97b4371804…

MALICIOUS

PDF

93.7 KB Created: 2021-09-15 17:48:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0e1bb6d6cc1530391d06ae0a6b396af9 SHA-1: 20b32707653ab3d08ac53a1f17867061e1e23729 SHA-256: 0b4c4f97b437180491cfbc507e0f63193cd85f380bc81486259cefca78f1e4eb
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF sample was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous external URLs, many pointing to disposable domains and employing UTM parameters, suggests a link farm or phishing lure designed to redirect users to potentially harmful content. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly indicate it's designed to exploit vulnerabilities or trick users into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://kalyna.ua/sites/default/files/userfiles/file/96927716915.pdf In PDF document text
    • https://ourcampuswindow.com/ckfinder/userfiles/files/kemegefudosiveradinijum.pdfIn PDF document text
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/zimusavavupun.pdfIn PDF document text
    • http://floridare.ru/app/webroot/img/uploads/file/234805_42620129520.pdfIn PDF document text
    • http://kronospan-mofa.hu/editor_up/89925161161.pdfIn PDF document text
    • http://xn--b1adrijbbb.xn--p1ai/upload_picture/varorix.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5c6875f39---nupubufesitumogedofijibun.pdfIn PDF document text
    • http://zjbfjt.com/upload/files/mimaliwifudojukejerugofoz.pdfIn PDF document text
    • http://rivebistro.net/ckfinder/userfiles/files/80483931432.pdfIn PDF document text
    • http://gainliving.com/upload/editor/file/jiloriwup.pdfIn PDF document text
    • https://soccerauquebec.com/userfiles/file/dusejalesazarejodomonaza.pdfIn PDF document text
    • https://znalac.com/userfiles/file/rofuvuvajeketojewebupi.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/90154711096.pdfIn PDF document text
    • http://herium.net/FileData/ckfinder/files/20210910_7581EE3C329638F7.pdfIn PDF document text
    • http://infinity-pro.ru/userfiles/file/bezateregamonaz.pdfIn PDF document text
    • http://nhakhoasaigonkimcuong.com/uploads/images/files/vuwenipovu.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/86168137756.pdfIn PDF document text
    • http://riverside-plaza.com/upload/userfile/files/9626088588.pdfIn PDF document text
    • http://pietrek.com/MARCUS/files/file/kabujapupobubamobavi.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613905cfa6cc9---pexerexemek.pdfIn PDF document text
    • https://ubk-sad.de/azubi/userfiles/files/2894099988.pdfIn PDF document text
    • http://resortcrimea.com/ckfinder/userfiles/files/posukudu.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/34207815730.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=never+let+me+go+full+movie+with+english+subtitlesPDF 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_off0001012d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1012D 10868 bytes
SHA-256: e51066869abcf18a16f07233e0991bc0f0ffe4ceaa8a5297760cdcf9842fd1c1
font_01_sfnt_off00011a27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A27 20824 bytes
SHA-256: b50e854328ff4d21cbf85e3123e0daaa378f6935e2ae8d7baa6294e41f2a8030
font_02_sfnt_off000150df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1