Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f9cc3b6ec1e6d95…

MALICIOUS

PDF

67.6 KB Created: 2020-11-11 05:44:28 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: aa7f8e941661c4f53e4345641ea6c079 SHA-1: 93c773e7edbc8b8a6135cd29ab9d6385ac845077 SHA-256: 5f9cc3b6ec1e6d95358657ae0654434667226fd4bbbe4b3e952add14f45a8876
214 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, with one identified as a known malicious redirector. The heuristic firings indicate a malicious redirector and a link farm, suggesting the document is designed to lead users to potentially harmful content. The ML classifier and ClamAV detection further support its malicious nature. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://cctraff.ru/strik?keyword=music+intervals+worksheet+pdf
    • https://cdn-cms.f-static.net/uploads/4424996/normal_5fa0ccad9812b.pdf
    • https://cdn-cms.f-static.net/uploads/4413851/normal_5fa2d1f5b3df0.pdf
    • https://cdn-cms.f-static.net/uploads/4374704/normal_5f9c5ab7f3ade.pdf
    • https://cdn-cms.f-static.net/uploads/4383795/normal_5f8f985a1f83b.pdf
    • https://cdn-cms.f-static.net/uploads/4373008/normal_5f8fb6bfabe81.pdf
    • https://cdn-cms.f-static.net/uploads/4387933/normal_5f97e8f321a05.pdf
    • https://cdn-cms.f-static.net/uploads/4418777/normal_5fa4649cdc620.pdf
    • https://sujibume.weebly.com/uploads/1/3/4/4/134442643/c72789b6.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/tesasubawalozan/dinawakonevosos.pdf
    • https://s3.amazonaws.com/tometubufimopim/bloodlines_book_4_read_online.pdf
    • https://s3.amazonaws.com/fizup/bfa_leveling_guide_1_120.pdf
    • https://s3.amazonaws.com/sugowubuf/36265555342.pdf
    • https://s3.amazonaws.com/rebomedug/41484899753.pdf
    • https://s3.amazonaws.com/zaxuledo/st_james_parish_schools_in_la.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c948.bin
b7c9150eb28d6d791c1ff7ece0543db910290e80de196b33ee1e7e34e469fe5c
pdf-font-stream PDF embedded font (sfnt) at offset 0xC948 5464 bytes
font_01_sfnt_off0000dbfb.bin
383bb3545a14dca6675f17d377b25c023a4b1dedc90c284c3394dd97ffbb9964
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFB 11336 bytes