Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4f2c639ad083fda…

MALICIOUS

PDF

77.6 KB Created: 2021-09-09 00:28:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 44b1daee9889418089626cff386bd676 SHA-1: 1126a93f20806501181d0f435580a1de7d1ff657 SHA-256: e4f2c639ad083fda705e562b7da2ede027e2260bae8776454663897418e4a957
134 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and a high ML classifier score, indicating malicious intent. The embedded JavaScript stream and external URI pointing to a link farm on disposable hosting suggest an attempt to trick users into downloading further payloads. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the phishing lure, presenting a deceptive facade for malicious downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://smidgel.ru/uplcv?utm_term=remote+desktop+client+for+android PDF link annotation
    • http://skontrolsengineering.com/file_media/file_image/file/sebeneresafovuxuvigite.pdfIn PDF document text
    • http://drivescuolaguida.it/userfiles/files/tuben.pdfIn PDF document text
    • https://shibbirs.com/media/files/tisojid.pdfIn PDF document text
    • http://berbun.com/user_img/file/39487379506.pdfIn PDF document text
    • http://fra2ange.it/userfiles/files/maxesajupozusuve.pdfIn PDF document text
    • http://sor1310.com/userfiles/file/nifalepedamozifak.pdfIn PDF document text
    • http://leeandrewdavison.com/download/takubonodaluwunixal.pdfIn PDF document text
    • http://www.bc-arman.kz/ckfinder/userfiles/files/tunilebaxesonuwateduwa.pdfIn PDF document text
    • http://mdfgiare.com/upload/files/81560650799.pdfIn PDF document text
    • http://destockbaby.com/ckfinder/userfiles/files/xivalazoturuli.pdfIn PDF document text
    • http://toshiteriyakiburien.com/uploads/files/3032175924.pdfIn PDF document text
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/35068458092.pdfIn PDF document text
    • http://tnslib.tools/userfiles/files/54384823041.pdfIn PDF document text
    • http://zaintik.org/files/galeria/files/95402151174.pdfIn PDF document text
    • http://thegioioto.store/upload/files/jepujaluvitepajejofu.pdfIn PDF document text
    • http://rootbeadmill.com/upload_fck/file/2021-9-6/20210906225157805274.pdfIn PDF document text
    • http://musclecar-taps.com/js/upload/files/85131114900.pdfIn PDF document text
    • http://kramnyca.info/img/upload/editor/file/47753318861.pdfIn PDF document text
    • https://istruttorecinofilo.it/userfiles/file/rasisujijufog.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1630950678.pdfIn PDF document text
    • http://cicm2015.mist.ac.bd/app/webroot/ckfinder/userfiles/files/84518421852.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/161328d8a4284a---96622103969.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139081ad0251---11835447686.pdfIn PDF document text
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/97266841893.pdfIn PDF document text
    • https://rhuyscampingcar.fr/images/files/43507922419.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_off0000ca60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA60 10920 bytes
SHA-256: 50f537e18fdebf08cfb0a02e1e6f9411a7a628c1611fa40b88a67e0095585093
font_01_sfnt_off0000e3a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A6 17320 bytes
SHA-256: 079748bb7bf61c6541f91e288e4efaa0b530e8bda27932b5684b1d931d95625b
font_02_sfnt_off00011058.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11058 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1