Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9cf03db1c7d2b39…

MALICIOUS

PDF

77.1 KB Created: 2021-09-19 16:16:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: cec244e64bbbec1ed1d4841e5d191bc6 SHA-1: 724e09c2eaf1ae89d65e27cb1faa66be9b18422a SHA-256: c9cf03db1c7d2b39a686a7b09c6ca2538b55bc9d44fb86caecca0438de9c9260
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. The presence of numerous embedded URLs, many pointing to PDF files on various domains, suggests a link farm designed to obscure the ultimate malicious destination. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM specifically indicates this pattern, likely intended to lure users into downloading malware disguised as legitimate content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161445a9e0815a---18072316195.pdf In PDF document text
    • https://solener.info/ckfinder/userfiles/files/87677177280.pdfIn PDF document text
    • https://nls.vn/upload/files/vadavawimawukikabu.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/pozavalojajiw.pdfIn PDF document text
    • https://urologasdainys.lt/userfiles/file/6858657398.pdfIn PDF document text
    • https://okud-istra.hr/userfiles/file/disepezogiwokanodopixe.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/vazaxixedinupobamive.pdfIn PDF document text
    • http://hengtongrongshang.com/jingkelun/userfiles/files/20210911221614.pdfIn PDF document text
    • http://arredamenticucinesiciliane.it/userfiles/files/47349363641.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/63328085981.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141d87c4d2b4---31790771114.pdfIn PDF document text
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/6270236366.pdfIn PDF document text
    • http://cdwy028.com/uploadfile/file/20210911062446.pdfIn PDF document text
    • http://retailcop.ca/files/22397607462.pdfIn PDF document text
    • http://yljczl.com/uploadfile/20210901081757803.pdfIn PDF document text
    • https://www.cdsale.org.au/application/third_party/ckfinder/userfiles/files/vagovefezetigipifitazu.pdfIn PDF document text
    • http://gpshardorawal.com/hemkunt/userfiles/file/gisisusivutawi.pdfIn PDF document text
    • http://thecountryclub32055.com/userimages/gejovepoziwojamosurez.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/86049212313.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/92179133875.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/43158918580.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-9-4/20210904064921352119.pdfIn PDF document text
    • http://eortak.com/img/fck_temp/file/16175974976.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=fifa+2020+offline+downloadPDF 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_off0000caa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAA9 17436 bytes
SHA-256: ba4fda13781eadb9e9b168b80cb09c9d3a5e94d40fb1cb7bc09a34244b7ef857
font_01_sfnt_off0000f73d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF73D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F54 10288 bytes
SHA-256: c3d40d2df67995c3b56d560d6ad3deda4fd3cf6b837e037b82379b4d19f4aeea