Malicious PDF — malware analysis report

Static analysis result for SHA-256 38b5891231d1bd32…

MALICIOUS

PDF

76.8 KB Created: 2021-04-02 15:41:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: c95ddf4a90fe7653df7d36cf9b5ad4a0 SHA-1: 5cc51c254f9f978e1f8ec6b9744814353c9a8f15 SHA-256: 38b5891231d1bd323b68088137720f496c531904879c9c04862af0f7d843a536
126 Risk Score

Malware Insights

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

The PDF document contains numerous external links, many hosted on disposable domains, suggesting a link farm designed to obscure the ultimate destination. The document body, though partially corrupted, indicates a lure related to a 'placement test'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 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://gimoguvi.ru/award?keyword=cambridge+unlimited+placement+test+pdf PDF link annotation
    • https://cdn.sqhk.co/telazaje/gchiggm/zig_zag_cones_price.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4455657/normal_5fe293468cd5e.pdfIn PDF document text
    • https://guretaximijogu.weebly.com/uploads/1/3/0/7/130739376/kirobamusizo.pdfIn PDF document text
    • https://vunisanelebori.weebly.com/uploads/1/3/3/9/133999195/1561ab5f5f27.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4471988/normal_5fedd16ade58b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382408/normal_604f0910338ff.pdfIn PDF document text
    • https://nepuxobim.weebly.com/uploads/1/3/5/3/135304691/momoza.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373248/normal_605350360a3ec.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495034/normal_5fc827ceaaf1c.pdfIn PDF document text
    • https://cdn.sqhk.co/nevupediwix/hi8gfo4/bijodavasekuf.pdfIn PDF document text
    • https://dopotalufiru.weebly.com/uploads/1/3/4/6/134601398/suneruluna.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454045/normal_6044def16fca7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4373520/normal_5ff82425741c5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408596/normal_60620a896990f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495974/normal_605f391cdec8a.pdfIn PDF document text
    • https://cdn.sqhk.co/dodanadofu/6jjHjei/48425528892.pdfIn PDF document text
    • https://sowefitubi.weebly.com/uploads/1/3/1/4/131406610/1819095.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427282/normal_5fea008526fcd.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/mexijegedakol/32951698939.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f53b7375-c11d-40a8-bc7a-2821cf6731a5/4254106987.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2ae89933-48bd-4a40-9d44-7a7c18d7eedb/86145114537.pdfIn PDF document text
    • https://s3.amazonaws.com/befafuni/90739320234.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0990036b-9b23-478b-8b97-9853b16812d8/beginner_python_projects_github.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/13edfa64-35b1-4011-a458-4aa00d712865/unity_technologies_stock_ipo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/59361f0e-18d9-4e60-b1a2-d35f928d704a/matlab_increase_subplot_size.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_off0000ef14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF14 5520 bytes
SHA-256: 8ab2fa44deacd54a6d8dee29410bd8a1ebd19b47a50b43f6e69651bfccd4eaf7
font_01_sfnt_off000101b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101B7 10624 bytes
SHA-256: c81580be983a4418744931511ebfa8b9364ac403d50e5d934ded4525e41c9cc0