Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a3996ffce001c82…

MALICIOUS

PDF

79.3 KB Created: 2021-09-18 03:51:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f27d124f149c81bd6c3b7349aa5f2d8e SHA-1: dd3f2bb9497c2bf242c816d17599612a06978d05 SHA-256: 8a3996ffce001c82e629d697aea0d78a9c3dbdd7e396e9f0e5b6418fef17f172
126 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous external URIs, with one heuristic specifically identifying a link farm on disposable hosting. This suggests the PDF's primary purpose is to redirect users to a network of other malicious PDFs, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://we2meeting.com/ckfinder/userfiles/publics/files/sotij.pdf In PDF document text
    • https://toananhmedical.com/uploads/files/nonufiviberetuzuz.pdfIn PDF document text
    • https://taxforce.nl/userfiles/files/81903518482.pdfIn PDF document text
    • http://dpnovelty.com/upload/files/81337799155.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e06596efb4---9162781389.pdfIn PDF document text
    • https://stdtekstil.com/upload/ckfinder/files/bamerajifutewu.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/nadoxokisojikajaxasojurug.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/97375289107.pdfIn PDF document text
    • http://iuoooo.com/filespath/files/20210905041954.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/5b5d48ee814c2b1d680420cb50827a61/kifatilazuwid.pdfIn PDF document text
    • http://ugrctrani.it/userfiles/files/latoboketidepobuk.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/87261056867.pdfIn PDF document text
    • http://kastely-vacduka.hu/fileok/file/16585231406.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/wevok.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1613ee7cfcdeb1---87907451720.pdfIn PDF document text
    • http://reelproductionshd.com/userfiles/file/jeritadizawowavagibapap.pdfIn PDF document text
    • http://robedecreateur.com/img/files/fokewewodubeju.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/14/timuvamuwut.pdfIn PDF document text
    • https://faktxeber.com/resimler/files/bonem.pdfIn PDF document text
    • http://xn--54-dlcdkamdj4btild5b.xn--p1ai/ckfinder/userfiles/files/69975648027.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/xasum.pdfIn PDF document text
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/memaperadogaxenilemix.pdfIn PDF document text
    • http://irvinenott.co.uk/ckfinder/userfiles/files/67933541431.pdfIn PDF document text
    • http://longarmquiltingacadamy.com/fckeditor/userfiles/file/risugajokesakejulu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=pc+part+picker+android+appPDF 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_off0000d519.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD519 10388 bytes
SHA-256: 52824e0035f38d01879d9d1379d28a1f9a9cc5a7ea5e4f475a0454fe115484ef
font_01_sfnt_off0000ecb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB6 16444 bytes
SHA-256: ec318c1fefbf87776a8a20f3e06b36f4fb77abbbf92d88eed04eac5dab166559
font_02_sfnt_off0001171e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1171E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1