Malicious PDF — malware analysis report

Static analysis result for SHA-256 b57071de6acd3c4c…

MALICIOUS

PDF

82.1 KB Created: 2021-09-18 12:22:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 31583d6d445fd4fde8005dfc8b722941 SHA-1: 378bda184b283a96e2a86cc82ec1407d48f8260d SHA-256: b57071de6acd3c4c88bac26bd3a1918b7ef209db448789da464dfaa0e74bbcd5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm designed to obscure the true malicious intent. The presence of external URIs and the 'disposable link farm' heuristic indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://ehomerealestate.org/images/file/81125933459.pdf In PDF document text
    • http://osmed.cz/app/webroot/files/files/libivipawataribinusuw.pdfIn PDF document text
    • http://96stone.ru/userfiles/file/ziluwixepun.pdfIn PDF document text
    • http://ylpcl.com/ckfinder/userfiles/files/29446609191.pdfIn PDF document text
    • http://xpeedon.net/userfiles/file/20210906135450.pdfIn PDF document text
    • https://maxlinder.com/admin/assets/ckfinder/userfiles/files/derodipiludose.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/vobamabisujotatid.pdfIn PDF document text
    • https://metrosecuritynepal.com/assets/userfiles/files/jopefe.pdfIn PDF document text
    • http://vektor-bezpeki.com/userfiles/files/lixepu.pdfIn PDF document text
    • http://trips-in.com/ckupload/files/12221848269.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b62925282b---95456295217.pdfIn PDF document text
    • https://termokingbt.com/ckfinder/userfiles/files/fudozu.pdfIn PDF document text
    • http://nusratali.com/userfiles/files/najukotubifutovutamefaw.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/025cd079b92a421df77ce682356bebd2/38742648162.pdfIn PDF document text
    • http://sanarina-coaching.de/ckfinder/userfiles/files/12789669115.pdfIn PDF document text
    • http://www.dilipprabhavalkar.com/images/file/detupizonetojububu.pdfIn PDF document text
    • http://hongsung114.com/files/fckeditor/file/384931556.pdfIn PDF document text
    • http://www.sudaff.com/pics/file/tufodukavexusuvowa.pdfIn PDF document text
    • https://polresseluma.com/assets/ckfinder/core/connector/php/uploads/files/67747592756.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/tafuxupikozidomufor.pdfIn PDF document text
    • http://pileki.com/imgup/file/zivugejenazopigeduvonive.pdfIn PDF document text
    • http://poiskvod.ru/images/file/paxujomokunijemer.pdfIn PDF document text
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/92038198280.pdfIn PDF document text
    • https://facades-et-traditions.com/actualites/file/luwuno.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/76408824984.pdfIn PDF document text
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/wimezadem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=punjabi+movies+download+hd+1080p+free+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_off0000d9c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C8 17692 bytes
SHA-256: 6bf2e02fa93d18239daadbcdf4360961224f7bd36e34fc05e473e34b98a77810
font_01_sfnt_off00010776.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10776 11572 bytes
SHA-256: 503309cf69ea3079cf18a160c7478cc0fc8e6d45c6eaa3e8a38680e5efd6b04b
font_02_sfnt_off00012283.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12283 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1