Malicious PDF — malware analysis report

Static analysis result for SHA-256 427cf7e8ec766c52…

MALICIOUS

PDF

69.2 KB Created: 2021-01-06 09:07:30 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: dfa6cd0db08b25ee240ca08f23190b58 SHA-1: cc530bb8a1b48c4a7805bc02fa3273ca606934ff SHA-256: 427cf7e8ec766c52245c5c39258edac4e96c72dad2a7292275009852dc329b4c
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to PDF files, indicative of a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing or malware hosting sites. While no scripts were explicitly extracted, the PDF structure and numerous external URIs suggest it's designed to exploit users' trust by appearing as legitimate content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://trafffi.ru/aws?utm_term=math+worksheets+for+grade+2+number+line PDF link annotation
    • https://dezilitew.weebly.com/uploads/1/3/4/7/134728488/5065186.pdfIn PDF document text
    • https://cdn.sqhk.co/novupezezis/cJQfWgc/beat_smash_color-_beat_color_circles_free_games.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408713/normal_5fa76e7751bdc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389568/normal_5fb58db7445ed.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4492880/normal_5feb4a6edc898.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418791/normal_5f9f04868db54.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366646/normal_5fd23995be8a7.pdfIn PDF document text
    • https://bipinudaw.weebly.com/uploads/1/3/4/7/134718108/5eb22c890.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404310/normal_5f981f179fe81.pdfIn PDF document text
    • https://cdn.sqhk.co/pusutekexu/cgj8Wjd/dream_girlfriend_dates.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/xurixado/begave.pdfIn 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_off0000d0a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A2 5752 bytes
SHA-256: cae20c1d21d6852894aa7dd4918c37a154d74de684995d2b632e5b5fd33e3eff
font_01_sfnt_off0000e42c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE42C 10556 bytes
SHA-256: 6e70475b21c07bf7c5d741645679685034b533c0ad8bbe247b55030e3af46deb