Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b4173f9e9f267d8…

MALICIOUS

PDF

90.0 KB Created: 2021-07-04 23:59:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 600cb893a0bd0315b068cc31d2b35e1a SHA-1: aa3a0342b79027b01edd806dfc5a1a8c531b8bc2 SHA-256: 6b4173f9e9f267d88e7c621a2b1dad9620c161c1042d5d59d4fb043e3cde3653
156 Risk Score

Malware Insights

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

The file is identified as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories, suggesting a link farm designed to redirect users. The presence of these links and the overall structure indicate an attempt to lure users to malicious content, likely as part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a81829bc518---risupezowodilotejoja.pdf In PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/7d1154d76c013bc4f9cc020135e487db/manufi.pdfIn PDF document text
    • https://dgaspcsm.ro/ckfinder/userfiles/files/pafisoriditiru.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160add212df16a---tixolewoxevenudikereruwo.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/92283975025.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/d1e8800508af8d1de0adddc7e600d413/67493548249.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16079c940a0c75---kaxevuvo.pdfIn PDF document text
    • https://inverpalmas.site/aym_image/files/nudoxojoreluzogileke.pdfIn PDF document text
    • http://katyababash.com/images/uploads/file/bofapuvakotepudej.pdfIn PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/pujikime.pdfIn PDF document text
    • http://summithighschool1958.com/clients/71652/File/80049209158.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc493d063e---20180313201.pdfIn PDF document text
    • http://humboldthighclassof79.com/clients/1/19/19f040aad945c40a0acbd79abd3dc6cb/File/kinetomag.pdfIn PDF document text
    • http://jevades.com/aircraft/fckimages/file/bemozonuj.pdfIn PDF document text
    • https://realestateconnect.us/wp-content/plugins/super-forms/uploads/php/files/oglnfnie7i6fp3693b5t2k5ih7/boxiwatugidevanusi.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/ac09c868879f9f892421f184ba28b059/sodogejamavuzo.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/62608421336.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/ec3dec8119de7981935edf4d454bd5e9/98742272892.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/27623183836.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/5b75f339a584c7867d3aaec14ad7a7bd/nigajukosogubozupomed.pdfIn PDF document text
    • https://washlounge.in/ckfinder/userfiles/files/30340644772.pdfIn PDF document text
    • http://whitepurdeespires.com/clients/b/ba/ba703c466af5784ee38134b9d09df413/File/wejojudajobukok.pdfIn PDF document text
    • http://flygarfield.net/userfiles/file/wupekivone.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16082abaf3b365---lipoviwiniforazazi.pdfIn PDF document text
    • http://stattus.com/assets/file/57501815776.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=you+are+kiddingPDF 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_off0000f988.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF988 10284 bytes
SHA-256: 6087aac7564fe7b9c94d8a685cd904571473514e95048f66900e7f4f957a7809
font_01_sfnt_off00011088.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11088 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001289a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1289A 18588 bytes
SHA-256: 23674dc4e9e72422d569d3b9073466bf618d67988c2bdc8d0d8b958001f78757