Malicious PDF — malware analysis report

Static analysis result for SHA-256 cba721990c11ef1b…

MALICIOUS

PDF

81.1 KB Created: 2021-06-12 03:21:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: f8bbfb9b80b935d03ac1890a6d15f61e SHA-1: 9400b1089bf152242fa5cd2a9715b0c4a4007be6 SHA-256: cba721990c11ef1b8f5d5ab690d9e0fae0d0bbcd9e3101ea2c7df8a5c635bef3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to multiple compromised websites, likely intended to trick users into downloading malicious files. Heuristics indicate a high likelihood of phishing and malware based on ML classification and ClamAV detection. The document body is heavily obfuscated and appears to be junk data, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://archism.ru/uplcv?utm_term=lalitha+audios+love+mp3+songs+download PDF link annotation
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b45e5961d4e---zufurisi.pdfIn PDF document text
    • https://pk-kuepfer.ch/ckfinder/userfiles/files/14300004765.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ceb87aad68---murozitanizamufogodoxafet.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/68c69815f515ae52dff1a2b792d00068/tizodokarizotebozexigerom.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/danapirij.pdfIn PDF document text
    • https://aedwea.com/upload/foto/jobedixubigizaroxavumu.pdfIn PDF document text
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/e3ko6tg5akhp1sbrlf0cup0a2e/rupagixunukaveraka.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file/%5C/65141157883.pdfIn PDF document text
    • http://abwingssuffolk1.com/uploads/files/levirapuzip.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097883d05ab6---xomixiz.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/81c77c8c52d5105d30737f6e638f7cc0/sesezumupivigolimitazono.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086788952d2e---wivevubakidob.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/a3a7eaed93391d123979544abed15f11/60392140721.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/jekusaj.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/215f12f58e957bab4b1b68b4a56b177a/77183940093.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/b1aa87485708dbf5d4eabc97e14086c6/lirevisewunevomomomev.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/1004ttf8sgiv6tu29i4nl83cdn/zadinotimemafolonetetin.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/3e82b15353350eb578efc86c0df792e8/fapovefokivitupatutidixo.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_off00010269.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10269 5532 bytes
SHA-256: 089549a56608c0a78d4cb5ae42ea8efcacd85db7b1a334909b2924054b323c96
font_01_sfnt_off00011530.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11530 10300 bytes
SHA-256: a361cbccbe50493db09d5e537d18f790749af4bbb277d99a37e24d2895d3e059