Malicious PDF — malware analysis report

Static analysis result for SHA-256 6124af945a65abd4…

MALICIOUS

PDF

81.5 KB Created: 2021-09-10 10:17:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8855639a7f83398724378d8559c3555c SHA-1: 4a781691acb589247166adba69ad374a9f6cd269 SHA-256: 6124af945a65abd4f8c3478400bfa1a2efc070ac80994ca449445a9d7ea93377
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. The embedded URLs point to various domains, suggesting an attempt to redirect users to potentially harmful content. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://tiyuchangdi.com/upload_files/files/20210901_073832.pdf In PDF document text
    • http://dr-onesrl.com/userfiles/files/fevalokumarajefelofiromon.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/20831739520.pdfIn PDF document text
    • https://mirrorlink.com/public/files/files/41136917060.pdfIn PDF document text
    • http://hrampetraipavlavosstanovlenie.ru/content/images/user/file/vizizudoxelolemojuri.pdfIn PDF document text
    • https://prestinieurope.com/userfiles/files/32112564211.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/67663267379.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/593e9c22a1663bb119753c0a9ce77208/43780372164.pdfIn PDF document text
    • http://canvangdientu.com/images/file/fovasamojuzan.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/nipesevu.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/xotujikigerozotiwazibi.pdfIn PDF document text
    • http://iowatriallawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vabijizukatumuj.pdfIn PDF document text
    • http://nachhilfeschule.havonix.com/ckfinder/userfiles/files/tolemexixeritadut.pdfIn PDF document text
    • http://tiquital.com/documentos/file/vikekabisadep.pdfIn PDF document text
    • https://2winit.com/Files/files/85588246948.pdfIn PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210902_152053.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/37279446749.pdfIn PDF document text
    • http://toyotacri.com/userfiles/files/dekesewajikugizok.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/pimowavazilow.pdfIn PDF document text
    • http://federicozucchettiarchitetto.eu/userfiles/files/zuzoju.pdfIn PDF document text
    • http://abhinavabhishad.org/userfiles/file/80892519582.pdfIn PDF document text
    • http://gzcaifeilai.com/ckfinder/userfiles/files/202109020253391727.pdfIn PDF document text
    • http://tbff-bygg.se/img/files/geginumarevamusiza.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/dff4f65725c0928c9ca4e0dda0a66606/guvubagaxevatebuzomoz.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/70967949486.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=fall+guys+online+game+playPDF 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_off0000d8ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C0 18352 bytes
SHA-256: 94ecbf00ab7e0d866b2ca50c89e2dcc2d9f41a50c45d82dfca4fbaa84ba51ebb
font_02_sfnt_off00011feb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FEB 10588 bytes
SHA-256: 73ebce093020c810413dccfb3d45778d079a667e619d73cffdd0bb17ea19ba32