Malicious PDF — malware analysis report

Static analysis result for SHA-256 6857ed84c2737e16…

MALICIOUS

PDF

77.0 KB Created: 2021-05-29 11:26:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: d74438703765a8808c1a215177d5eb7e SHA-1: 25868d197cc6c51d4cf8e24c77000315ae9d70c4 SHA-256: 6857ed84c2737e1629d021e50aff4a088dbd78bc88c14769fa4675d75c7b153b
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The document body's title, 'Qual e o segredo para ganhar na mega sena' (What is the secret to winning the mega sena), indicates a lure for potential victims interested in lottery scams. ClamAV detection and ML classification further confirm its malicious nature, likely as a phishing or malware distribution vector.

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://synerhu.ru/uplcv?utm_term=qual+e+o+segredo+para+ganhar+na+mega+sena PDF link annotation
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160745ea7ad3fd---95815704692.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/rejugudupolawawuwolakiwo.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160909931f3b9e---71276903828.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1609b6c5951ccb---sukawejawebedog.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/2d0498a666eae5e747107f266c0e1d9e/3199333277.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160b19c2274de9---33876024020.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/d4fd777eeb250b4990e0a1cfd375a83e/80317123105.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/696e66cd958b14c634a9bcfe8d117ac6/89860762355.pdfIn PDF document text
    • https://akarchlight.com/wp-content/plugins/super-forms/uploads/php/files/510a9d3e6a635cf713175363b3715fff/buvugizoko.pdfIn PDF document text
    • http://lideparts.com/userfiles/file/1621281527.pdfIn PDF document text
    • http://airsoft1.ro/files/file/50917858217.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6b0027725---28904059306.pdfIn PDF document text
    • https://ipic.vn/userfiles/file/niwataka.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092eff31171b---gutibitatedozodukofol.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_off0000ec11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC11 5432 bytes
SHA-256: 06c0fd487b54c83c2fd5cb8bfb5b541c4f0b09ad44223f35c1282f53b6c34037
font_01_sfnt_off0000fe5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE5B 12632 bytes
SHA-256: 4a615eb8c0d51034631862e6ee120684e5bc2ccc665d9edffd56e5ed99bc9d0b