Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ff0d3c4fc8eb751…

MALICIOUS

PDF

78.4 KB Created: 2021-05-21 17:43:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 85269d90a22e4fc24baa823cbb7b79dc SHA-1: 2a0868cba47248f1a4b406ec7e0bb81afd03881b SHA-256: 4ff0d3c4fc8eb7517aa3909e91bb866140586ead83f0bc8e34a7646343193d7d
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous embedded URLs point towards a malicious document designed to redirect users to potentially harmful sites.

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
  • 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.
  • 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://ponafet.ru/strik?utm_term=how+to+do+double+sequential+defibrillation PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4420431/normal_60213f778f0eb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372080/normal_6037c4a87efcc.pdfIn PDF document text
    • https://panejukirid.weebly.com/uploads/1/3/1/6/131606092/2a15be09e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371003/normal_5ffbde5413267.pdfIn PDF document text
    • https://lovebaxubifutu.weebly.com/uploads/1/3/4/3/134322000/2329937.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412894/normal_600d0225e246f.pdfIn PDF document text
    • https://sulidisige.weebly.com/uploads/1/3/4/3/134318683/xidudaromadexuxamev.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379233/normal_60619cf64e2f3.pdfIn PDF document text
    • https://bawapumur.weebly.com/uploads/1/3/4/4/134466187/9229706.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501998/normal_5fe774596908e.pdfIn PDF document text
    • https://kelurefuvaw.weebly.com/uploads/1/3/0/9/130969237/3835625.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368971/normal_601e2ff7b27cd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414501/normal_606eaa818ce2d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2180ab7-f2c5-4efa-af92-cc291028c004/98231555349.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/961404d6-8cf9-43ca-a733-944828e9b7d0/gigozifotuwujizun.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/99455838-ad25-4402-9ec0-39bb31f7229b/25068790076.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f94552b4-ec2a-4fbe-9050-df9b300445e3/52690983905.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b95bd2c7-1fc7-4b84-92b6-8668852d4a38/what_is_the_need_of_value_education.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f6e2273a-15bb-4bb9-b50d-195a1aec142c/xaxuzaravemex.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_off0000f421.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF421 5220 bytes
SHA-256: c0eec6a6d9a8a78d28eb18b738d74e5f76a2b38884e16db4b65f03876a01aa06
font_01_sfnt_off000105f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105F9 11224 bytes
SHA-256: 3d76b09e28fc979c00d13d28374c9818596da07bebe5a773ef61909a3fe6d328