Malicious PDF — malware analysis report

Static analysis result for SHA-256 54933eb3121a7549…

MALICIOUS

PDF

76.2 KB Created: 2021-06-18 22:28:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: e1f0effad91a8cec885b43b4e815ffa5 SHA-1: 60acc5324740b4bbbafd5b59ebf2dd72104c467d SHA-256: 54933eb3121a7549f6f3bb0762707af76adb8078605e77e6caeb0184c8c2325e
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The sample is a PDF document flagged by ML classifiers and ClamAV as malicious. It contains multiple external URLs, some pointing to compromised WordPress sites, suggesting a link farm or distribution point. The 'SE_BROWSER_INSTALL_LURE' heuristic indicates the document's content is designed to trick users into installing software, a common social engineering tactic for malware delivery or credential harvesting. No scripts were extracted, but the PDF structure and heuristics point to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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=book+10+test+2+writing+task+1 PDF link annotation
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/e8106fcd1131f77f497f0a016d154c1f/49312747953.pdfIn PDF document text
    • http://omegapizza.net/uploads/files/36017867365.pdfIn PDF document text
    • http://aaaexpressheating.com/userfiles/file/42846984861.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/11282472896.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/c51b9ea2023540c10656d9474a265d96/vovabonofadirojo.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/bh7vnnhfo9e8lgvfr59pkkasv3/zilemixaxakofipi.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e25567cc5a---vikemev.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16098633428c45---fijivu.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/bb26ef2e0eea1ffc79ebc40ba1e3a0cb/53934717544.pdfIn PDF document text
    • http://alituncer.com/userfiles/file/nabevozotenonadufuvuxuli.pdfIn PDF document text
    • https://tecnicadovolante.com/images/file/9672958420.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/21002679751.pdfIn PDF document text
    • https://marosme.ro/hirek/file/16104675583.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160771817e2c33---98133355512.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/6db17b717fda38a2dd57c81c4e55a9f7/77199939389.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB30 5352 bytes
SHA-256: c4a5e7dcc6f08555b65954b2c12246140eaee18e8b17cc26ca27af13d1d597e9
font_01_sfnt_off0000fd9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD9A 10780 bytes
SHA-256: f1b99b9b1a8cf49da2288e613f5d11ce7575acb02375722225b4b71af96a988a