Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8b841779079bbb6…

MALICIOUS

PDF

75.1 KB Created: 2021-04-05 00:08:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: d71fc5596576c2123a2e0296efed6a01 SHA-1: e3d47d7329620b782645e22bcfbad8d40930e6de SHA-256: a8b841779079bbb6f9e33399e5de7c1849ed2b62638c404b8dfc27aba2a6791e
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains a large number of external links, with one prominent URL pointing to a suspected SEO redirector or phishing page. The presence of these links suggests the document's primary purpose is to redirect users to potentially harmful websites, possibly for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://dugedepap.ru/123?utm_term=biafra+news+application PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4418970/normal_600e62356fcc2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4478683/normal_5fdec4dc69d45.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443356/normal_604393723e666.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374542/normal_5fd70460836e4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379240/normal_603719ee2bbb7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387924/normal_602cad345c17d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383797/normal_604544857e075.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4456121/normal_5fc965e338c7f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376854/normal_600dd940322d7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489056/normal_600a01e1532e4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380380/normal_5fd7eba06ff4c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410953/normal_6050325c47b9e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466135/normal_6047c14ad5f89.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474987/normal_602552eb0440a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477387/normal_60462f6d761f2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451376/normal_60263c83ca4bf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366407/normal_6060fef88b099.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://a6f18165-9bfd-46c9-8f51-0ab50cd0b687.filesusr.com/ugd/265c7a_9554097a299a404ba55a7c0824b4ae2c.pdf?index=trueIn PDF document text
    • https://39c10a3a-92c6-412a-a1bb-b8a1fc48fbc4.filesusr.com/ugd/259099_f07a27ca3a714f07aec85edd63c2b930.pdf?index=trueIn PDF document text
    • https://ff536187-e25a-4bd2-965b-ff1113cf40b0.filesusr.com/ugd/bfcccc_7f26f865284b4ed3a2b8c5705cd8776f.pdf?index=trueIn 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_off0000e9a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9A3 5152 bytes
SHA-256: 52350516d4a66ebf7fe04e012e9151d99eabd5a8394e2cee866ca715b763acb7
font_01_sfnt_off0000fb4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB4E 10488 bytes
SHA-256: 2116d9801a40d0691dfdc21f3586b60b46290cf99661d7c9b7d007eecac4d7e4