Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8a679a9e5e6c1fd…

MALICIOUS

PDF

72.5 KB Created: 2021-09-28 00:07:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e36837ebf5b11ba4cdf68f1b92aff209 SHA-1: 08bd129edfb48384a0609aa74accbb1ee189f91f SHA-256: b8a679a9e5e6c1fd2b034ed409fbb49afb8f63ad3786db3ce5229419044b96e1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the large number of embedded URLs suggest the document's primary purpose is to redirect users to potentially harmful external sites. No scripts were extracted, but the document structure itself is designed to host and present numerous links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://fitness-sport.it/userfiles/file/bikegopezexisimafevim.pdf In PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138dc7d944f1---ruwesiwejojebiribit.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/tiginukovuvusalodi.pdfIn PDF document text
    • http://eamenfaraz.com/cache/fck_files/file/18351663126.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/5ec70baef9bff78f7e847e8e111c919c/ralajevo.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/72105040912.pdfIn PDF document text
    • http://celcg.pl/uploaded/file/kezepolapupifif.pdfIn PDF document text
    • http://le-bouquet.be/userfiles/files/finudimefaduruniredubid.pdfIn PDF document text
    • https://webmenuplus.com/images/file/46423477967.pdfIn PDF document text
    • http://musthighschool.mn/ckfinder/userfiles/files/35610551287.pdfIn PDF document text
    • https://www.highettmetal.com.au/application/third_party/ckfinder/userfiles/files/6720962789.pdfIn PDF document text
    • http://turar-mussin.com/userfiles/File/67462956500.pdfIn PDF document text
    • http://bioaec.com/userfiles/files/899377995.pdfIn PDF document text
    • http://kahasat.cz/data/file/koronifewukesomudatal.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/tifox.pdfIn PDF document text
    • https://bem-sa.com/img/file/14163987485.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/71887985668.pdfIn PDF document text
    • https://penzion-palice.cz/content/dozajugadebujufu.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/13791821428.pdfIn PDF document text
    • http://dpsszczytno.pl/photo/file/90560382567.pdfIn PDF document text
    • https://comobrew.com/newsite/images/user_uploads/file/gaxenolebebabego.pdfIn PDF document text
    • http://vagyonvedelemszolnok.hu/admin/fck_upload/file/bedereraw.pdfIn PDF document text
    • http://biomehl.com/images/content/files/52660080275.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/fufenugorikilulitesenig.pdfIn PDF document text
    • http://meghdoothsuzuki.com/uploads/mebatewefesopakabon.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=mobdro+for+chromebookPDF 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_off0000b676.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB676 10296 bytes
SHA-256: 1294fe70ddc0c0edc2d172cff925b1b4cf145da4c36abf6a59848f2a84561cce
font_01_sfnt_off0000cd9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD9A 18200 bytes
SHA-256: 9de5a8e786212056a4a6094461c770ec5fb4cc83670b8143a76daec952658e1a
font_02_sfnt_off0000fca0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1