Malicious PDF — malware analysis report

Static analysis result for SHA-256 8851ec8c8eca7bf1…

MALICIOUS

PDF

74.7 KB Created: 2021-02-25 00:48:07 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 59803d0dfcab4c6184b36a59bdd74805 SHA-1: a455f262994be776305d4d93d7b327446266db19 SHA-256: 8851ec8c8eca7bf18fdb6463dd2f10ebbd3f51ffb385e53f8486ed1709cfe37e
156 Risk Score
Tags
free-cdn-ebook-manual-lure

Malware Insights

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

The PDF file contains a large number of external links, many of which point to other PDF files, suggesting a link farm or SEO manipulation tactic. The primary URL, https://crophysi.ru/strik, is likely part of a phishing or scam campaign, attempting to lure users with a seemingly innocuous definition. While no scripts were explicitly extracted, the PDF structure and numerous external links, combined with the ClamAV detection and ML classifier, strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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.
  • 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://crophysi.ru/strik?utm_term=database+management+software+definition PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4488346/normal_602ff53beaf4b.pdfIn PDF document text
    • https://foxesomi.weebly.com/uploads/1/3/0/7/130775893/letanemujonuzejal.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412415/normal_5fe24c27d8b35.pdfIn PDF document text
    • https://tokubarip.weebly.com/uploads/1/3/1/3/131380438/sugumumupojigonuruxo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465392/normal_6016f38a82b6c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4502567/normal_6029b38d6467e.pdfIn PDF document text
    • https://levobije.weebly.com/uploads/1/3/0/9/130969703/1730771.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4470405/normal_5ff1546f57111.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/juvetaso/handwriting_worksheet.pdfIn PDF document text
    • https://s3.amazonaws.com/tamobalasu/99198025282.pdfIn PDF document text
    • https://s3.amazonaws.com/matogapibelifiv/5096510913.pdfIn PDF document text
    • https://s3.amazonaws.com/bipepezuwed/medusa_s_garden_full_movie.pdfIn PDF document text
    • https://s3.amazonaws.com/petuzutemixuvod/78863848447.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA00 5212 bytes
SHA-256: 8bc8dd8a32609eee697d086f8971e46bc0ddaeca0cd20a68150fe7226cad1258
font_01_sfnt_off0000ebaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBAA 10648 bytes
SHA-256: b416be00977bfc5a60ea34f9dab3db228cd4c38365724ffb8dc9867f4bed29ed
font_02_sfnt_off00010fe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE5 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2

Open this report in the interactive analyzer, or submit your own file for analysis.