Malicious PDF — malware analysis report

Static analysis result for SHA-256 18e55d7bd65521b7…

MALICIOUS

PDF

96.8 KB Created: 2021-09-01 22:13:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 270ce23527403fed4928f3d93ed899cb SHA-1: 0d5dc3efd9c059e341fdb99ca9e6eb768ff77d1d SHA-256: 18e55d7bd65521b7fbbf9960f2e8454b4e2979cda5915de19b968cf5c6502974
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via these external links. No scripts were extracted, but the overall structure and URL analysis point to a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://crewmak.ru/uplcv?utm_term=plastic+paradise+the+great+pacific+garbage+patch+worksheet+answer+key PDF link annotation
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/c8d571e0e7345caa87dc5e6f8c77cda6/namexom.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ade4dc6b58e---fotuwe.pdfIn PDF document text
    • http://bilmatbasim.com/userfiles/file/1120349115.pdfIn PDF document text
    • https://mallncart.com/userfiles/files/55172979380.pdfIn PDF document text
    • http://bukharasuwanee.com/sites/default/files/file/24680957919.pdfIn PDF document text
    • https://alident.centralcms.cloud/galeria/files/zovotagep.pdfIn PDF document text
    • https://101doctor.com/uploads/ckfiles/files/60cb93b82d7a9.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606c971ae93db---83051337887.pdfIn PDF document text
    • http://trunghungplastic.com/luutru/files/miwilisedinuxogokibu.pdfIn PDF document text
    • http://gpba.ge/admin/ckeditor/ckfinder/userfiles/files/padakefu.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/8e8f6a1c480520c9cfe7b3e9918369d6/77434228787.pdfIn PDF document text
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/fc0161df1a078ad491ca7a6b5cd5b445/99908989121.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/15312852492.pdfIn PDF document text
    • http://mallenmediations.com/mallenmediations/images/userfiles/file/57205869496.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/d90999b72814a0b6098a8b3a87471575/duzimo.pdfIn PDF document text
    • http://konditsionery-reutov.ru/upload_picture/file/65360298989.pdfIn PDF document text
    • http://kwong-cheong.com/userfiles/wefivedajaru.pdfIn PDF document text
    • https://nulifeus.com/~nulife/userfiles/file/59329096832.pdfIn PDF document text
    • http://brkvinc.com/userfiles/file/xonibuwizobuzazuwex.pdfIn PDF document text
    • https://ekoelprom.pl/public/images/editor/file/21147134106.pdfIn PDF document text
    • https://miet.hu/kepek/baradovonubupu.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/sobefokarijesijozanesefa.pdfIn PDF document text
    • https://j26clean.com/upload/files/35292041745.pdfIn PDF document text
    • http://dhf-china.com/d/files/6931538279.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_off00010f97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F97 19232 bytes
SHA-256: 4d1ee6052cd0acd6c17decde41788636951f61ff828c1b3785c028517792e0b4
font_01_sfnt_off000141b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000159c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x159C7 11332 bytes
SHA-256: dd4ce6b5e07fa58fafe3a8a5a991d80d7fa88a936cc2a6314f66731074fffdd1