Malicious PDF — malware analysis report

Static analysis result for SHA-256 5fb6ab4b30644b97…

MALICIOUS

PDF

77.6 KB Created: 2021-05-26 16:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 9de96ffb3b833ae00b7e20922a5a60f7 SHA-1: 2b7d7d16cae3768d87ce43723676de8a32e50dee SHA-256: 5fb6ab4b30644b97478c2d03446e82c19f520c70aac0af420c9caed0c45c3a88
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 pointing to disposable hosting, suggesting a link farm designed to drive traffic. The primary URL, 'https://druttle.ru/strik?utm_term=free+android+unlocking+software+download', indicates a lure for users seeking free software, likely to redirect them to malicious content or phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://druttle.ru/strik?utm_term=free+android+unlocking+software+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4372702/normal_60669676f1201.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426423/normal_5fee7fef5225c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457862/normal_605fed63dd987.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412767/normal_5fd89603ee4e0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369671/normal_601f8f26c0eb5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445321/normal_60418c37890f0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475564/normal_60663e15864bf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418968/normal_5fd2615006727.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4471711/normal_5fe0402c7fea6.pdfIn PDF document text
    • https://gagoxesuv.weebly.com/uploads/1/3/2/6/132681450/7940776.pdfIn PDF document text
    • https://xujesosa.weebly.com/uploads/1/3/6/0/136090165/7377112.pdfIn PDF document text
    • https://panesiwosejel.weebly.com/uploads/1/3/0/7/130739396/c0794ed2.pdfIn PDF document text
    • https://dukilukisa.weebly.com/uploads/1/3/1/0/131070258/wutowilefe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4492546/normal_605153568d29f.pdfIn PDF document text
    • https://bewevirat.weebly.com/uploads/1/3/1/4/131437926/novumok.pdfIn PDF document text
    • https://bexusisase.weebly.com/uploads/1/3/4/5/134596812/f5db7254eb3f.pdfIn PDF document text
    • https://ruvawuwejijexut.weebly.com/uploads/1/3/0/8/130814193/1f603be6db0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390371/normal_60450977c2f34.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490516/normal_6060f4f61352f.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/1a7c2f66-f953-424c-8c0f-207891c13eea/golakimad.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/86c44ab6-9c82-4792-beb7-4a391551d2cb/20696031195.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c1bded2-b617-4f52-a47a-85f82b40ba9e/85181335035.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6e44b279-7cb7-4959-88ac-537ed125fcd9/wikobugiwerivizobu.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_off0000f20e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF20E 5300 bytes
SHA-256: 2d46f720bb60e00a3d6c5e7dc672e2da81126e097c28f798fea841c736672dbb
font_01_sfnt_off0001043a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1043A 10660 bytes
SHA-256: dfadf53c7cdf8734655315e3bf62f9107bd5f87ec31531a3f612d66cd9515363