Malicious PDF — malware analysis report

Static analysis result for SHA-256 91dc9776b2dec3b2…

MALICIOUS

PDF

107.5 KB Created: 2021-06-09 13:27:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: 567456f99e78ddfc5dcbcf0a06968fa3 SHA-1: 0b2488c7a9ded8c538ca428087ced0026b73d877 SHA-256: 91dc9776b2dec3b29227e93b7219dbf457a682e56323d75383072697a8d8e2b5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document body, though heavily obfuscated, contains references to 'gta san andreas cesar vialpando mission skip cheat', suggesting a lure to entice users to click on embedded links. Multiple heuristics indicate the PDF is part of a link farm hosted on compromised or disposable domains, likely serving as a distribution point for further malicious content.

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://coretry.ru/uplcv?utm_term=gta+san+andreas+cesar+vialpando+mission+skip+cheat PDF link annotation
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1608c492057f0f---47430887070.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/59346726147.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/th9liv4aoamd9k7eljupeiphh0/noxiveme.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0db3ca330---xewumutelegi.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/116f55b108f654824b8ea814d5cb9b2f/tararunegonawokesubavoze.pdfIn PDF document text
    • http://j-line.ca/fck_upload/file/zexuxoximerabujaf.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/94377255030.pdfIn PDF document text
    • http://stalmost.pl/userfiles/file/29780772958.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b23319f57---68229550650.pdfIn PDF document text
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd5ca1f245---nogidonapa.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/6krkant96o0t98g2j45thq6m5g/falikukevofagisexep.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608651ea24613---54474007823.pdfIn PDF document text
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/n7os7fud7nc6uu06dh23m2r2fr/90489135181.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074bfd488c97---19208222113.pdfIn PDF document text
    • https://clifestyle.net/uploades/userfiles/file/31320636733.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_off000168b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x168B0 5468 bytes
SHA-256: 7ceff29fbf280d9fa137b0ad509c10b1807066e81eed8dc750c0883982ed3cf7
font_01_sfnt_off00017b26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17B26 11076 bytes
SHA-256: 328f44c51f91e7bba8d84dce6bee46baf4725e75c9c5c8317b580e21785d9268