Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cdd8f5cce0dbc8d…

MALICIOUS

PDF

70.3 KB Created: 2021-09-24 23:17:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6e7bed9f1cc52ed7dbc1931d83c10374 SHA-1: 2c2391d267574a81f76f3815f129eaa3e51fdd24 SHA-256: 9cdd8f5cce0dbc8db6762d84a3561f1e457d27f2396b9e1d582939959b9f2001
74 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, indicating an attempt to redirect the user to malicious websites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests a large number of links pointing to disposable hosting, reinforcing the malicious intent. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is designed to exploit users, likely through social engineering or by serving a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

Heuristics 5

  • 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://nomylo.ru/uplcv?utm_term=system+ui+has+stopped+on+tablet PDF link annotation
    • http://planao.com/ckfinder/userfiles/files/91475109050.pdfIn PDF document text
    • http://cartopack.be/Images/file/56191732087.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/pelarulubu.pdfIn PDF document text
    • http://arenda-v-novosibirske.ru/ckfinder/userfiles/files/32632691630.pdfIn PDF document text
    • http://aasghsflqsae.handylover.com/upload/files/93752319808.pdfIn PDF document text
    • http://nerezove-kuchyne.cz/UserFiles/File/vuviv.pdfIn PDF document text
    • http://celcg.pl/uploaded/file/momebasonirumavotag.pdfIn PDF document text
    • http://sirindhorn.net/upload/File/vetanisobilajowavuvurex.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/zimeteduvosonirajopezo.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/17978911718.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/25177424871.pdfIn PDF document text
    • https://interior-mark.com/ckfinder/userfiles/files/20992190465.pdfIn PDF document text
    • https://doitoutdoorz.com/file/JPgXEOhCaOu9z3zj.pdfIn PDF document text
    • http://thegioimaychaybo.com/app/webroot/uploads/files/kidalurogaxifoko.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/wobaneserezotugo.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/49a89250bcdfbaf5a0e0a5775c06821c/81482983803.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161427aa080c65---zewameseruzasobefigavo.pdfIn PDF document text
    • http://trunglam.vn/uploads/userfiles/file/zopatisoroxikejexojukutu.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/pinopif.pdfIn PDF document text
    • https://decisionstogo.com/fck_image/file/pidizapotuxovujogixepa.pdfIn PDF document text
    • https://manpowernepal.net/ckfinder/userfiles/files/fujotemim.pdfIn PDF document text
    • http://worthingtonpark101.com/userimages/65239724359.pdfIn PDF document text
    • http://geometracosentino.com/userfiles/files/xoziparopune.pdfIn PDF document text
    • http://barsugo.com/ckfinder/userfiles/files/45164960685.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/90533592958.pdfIn PDF document text
    • http://stylowa-pss.pl/userfiles/file/fuzamefuvejeviturovela.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_off0000b32a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB32A 15612 bytes
SHA-256: a49f5b8c3160b09581685d8dff5efe686672906acaca2214824ef8b38874997f
font_01_sfnt_off0000dab9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAB9 10988 bytes
SHA-256: e85f52626ead98b77a23c5763e25386808fb7c9abfbf7a08a940ce3066caed69
font_02_sfnt_off0000f3d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1